<?xml version="1.0" encoding="US-ASCII"?>
<!--XBRL Document Created with Wdesk from Workiva-->
<!-- -->
<link:linkbase xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <link:roleRef roleURI="http://www.costar.com/role/Acquisition" xlink:href="csgp-20171231.xsd#Acquisition" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/AcquisitionAcquisitionDetailsScheduleOfAssetsAcquiredAndLiabilitiesAssumedForApartmentFinderDetails" xlink:href="csgp-20171231.xsd#AcquisitionAcquisitionDetailsScheduleOfAssetsAcquiredAndLiabilitiesAssumedForApartmentFinderDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/AcquisitionDetailsForApartmentFinder" xlink:href="csgp-20171231.xsd#AcquisitionDetailsForApartmentFinder" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/AcquisitionPolicies" xlink:href="csgp-20171231.xsd#AcquisitionPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/AcquisitionTables" xlink:href="csgp-20171231.xsd#AcquisitionTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/CommitmentsAndContingencies" xlink:href="csgp-20171231.xsd#CommitmentsAndContingencies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/CommitmentsAndContingenciesDetails" xlink:href="csgp-20171231.xsd#CommitmentsAndContingenciesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/CommitmentsAndContingenciesPolicies" xlink:href="csgp-20171231.xsd#CommitmentsAndContingenciesPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/CommitmentsAndContingenciesTables" xlink:href="csgp-20171231.xsd#CommitmentsAndContingenciesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/ConsolidatedBalanceSheets" xlink:href="csgp-20171231.xsd#ConsolidatedBalanceSheets" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/ConsolidatedBalanceSheetsParenthetical" xlink:href="csgp-20171231.xsd#ConsolidatedBalanceSheetsParenthetical" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/ConsolidatedStatementsOfCashFlows" xlink:href="csgp-20171231.xsd#ConsolidatedStatementsOfCashFlows" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/ConsolidatedStatementsOfComprehensiveIncomeLoss" xlink:href="csgp-20171231.xsd#ConsolidatedStatementsOfComprehensiveIncomeLoss" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/ConsolidatedStatementsOfOperations" xlink:href="csgp-20171231.xsd#ConsolidatedStatementsOfOperations" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/ConsolidatedStatementsOfStockholdersEquity" xlink:href="csgp-20171231.xsd#ConsolidatedStatementsOfStockholdersEquity" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/DocumentAndEntityInformation" xlink:href="csgp-20171231.xsd#DocumentAndEntityInformation" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/EmployeeBenefitPlans" xlink:href="csgp-20171231.xsd#EmployeeBenefitPlans" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/EmployeeBenefitPlansDetailsForEmployee401KPlanEmployeePensionPlanRegisteredRetirementSavingsPlanAndEmployeeStockPurchasePlan" xlink:href="csgp-20171231.xsd#EmployeeBenefitPlansDetailsForEmployee401KPlanEmployeePensionPlanRegisteredRetirementSavingsPlanAndEmployeeStockPurchasePlan" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/EmployeeBenefitPlansDetailsForStockIncentivePlans" xlink:href="csgp-20171231.xsd#EmployeeBenefitPlansDetailsForStockIncentivePlans" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/EmployeeBenefitPlansPolicies" xlink:href="csgp-20171231.xsd#EmployeeBenefitPlansPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/EmployeeBenefitPlansTables" xlink:href="csgp-20171231.xsd#EmployeeBenefitPlansTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/FairValue" xlink:href="csgp-20171231.xsd#FairValue" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/FairValueDetails" xlink:href="csgp-20171231.xsd#FairValueDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/FairValueTables" xlink:href="csgp-20171231.xsd#FairValueTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/Goodwill" xlink:href="csgp-20171231.xsd#Goodwill" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/GoodwillDetails" xlink:href="csgp-20171231.xsd#GoodwillDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/GoodwillTables" xlink:href="csgp-20171231.xsd#GoodwillTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/IncomeTaxes" xlink:href="csgp-20171231.xsd#IncomeTaxes" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/IncomeTaxesDetailsComponentsForProvisionForIncomeTaxes" xlink:href="csgp-20171231.xsd#IncomeTaxesDetailsComponentsForProvisionForIncomeTaxes" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/IncomeTaxesDetailsComponentsOfDeferredTaxAssetsAndLiabilities" xlink:href="csgp-20171231.xsd#IncomeTaxesDetailsComponentsOfDeferredTaxAssetsAndLiabilities" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/IncomeTaxesDetailsOther" xlink:href="csgp-20171231.xsd#IncomeTaxesDetailsOther" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/IncomeTaxesDetailsReconciliationOfProvisionForIncomeTaxes" xlink:href="csgp-20171231.xsd#IncomeTaxesDetailsReconciliationOfProvisionForIncomeTaxes" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/IncomeTaxesDetailsUnrecognizedTaxBenefits" xlink:href="csgp-20171231.xsd#IncomeTaxesDetailsUnrecognizedTaxBenefits" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/IncomeTaxesTables" xlink:href="csgp-20171231.xsd#IncomeTaxesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/IncomeTaxesTaxCutsAndJobsActOf2017Details" xlink:href="csgp-20171231.xsd#IncomeTaxesTaxCutsAndJobsActOf2017Details" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/IntangibleAssets" xlink:href="csgp-20171231.xsd#IntangibleAssets" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/IntangibleAssetsDetails" xlink:href="csgp-20171231.xsd#IntangibleAssetsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/IntangibleAssetsTables" xlink:href="csgp-20171231.xsd#IntangibleAssetsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/Investments" xlink:href="csgp-20171231.xsd#Investments" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/InvestmentsAvailableForSaleSecuritiesDetails" xlink:href="csgp-20171231.xsd#InvestmentsAvailableForSaleSecuritiesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/InvestmentsPolicies" xlink:href="csgp-20171231.xsd#InvestmentsPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/InvestmentsScheduledMaturitiesAndRealizedGainsAndLossesDetails" xlink:href="csgp-20171231.xsd#InvestmentsScheduledMaturitiesAndRealizedGainsAndLossesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/InvestmentsTables" xlink:href="csgp-20171231.xsd#InvestmentsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/LongTermDebt" xlink:href="csgp-20171231.xsd#LongTermDebt" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/LongTermDebtDetails" xlink:href="csgp-20171231.xsd#LongTermDebtDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/LongTermDebtDetailsComponentsOfLongTermDebt" xlink:href="csgp-20171231.xsd#LongTermDebtDetailsComponentsOfLongTermDebt" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/LongTermDebtDetailsCovenantCalculations" xlink:href="csgp-20171231.xsd#LongTermDebtDetailsCovenantCalculations" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/LongTermDebtDetailsInterestExpenseAndAmortizationOfDebtIssuanceCosts" xlink:href="csgp-20171231.xsd#LongTermDebtDetailsInterestExpenseAndAmortizationOfDebtIssuanceCosts" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/LongTermDebtTables" xlink:href="csgp-20171231.xsd#LongTermDebtTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/NetIncomeLossPerShare" xlink:href="csgp-20171231.xsd#NetIncomeLossPerShare" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/NetIncomeLossPerShareDetails" xlink:href="csgp-20171231.xsd#NetIncomeLossPerShareDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/NetIncomeLossPerSharePolicies" xlink:href="csgp-20171231.xsd#NetIncomeLossPerSharePolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/NetIncomeLossPerShareTables" xlink:href="csgp-20171231.xsd#NetIncomeLossPerShareTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/Organization" xlink:href="csgp-20171231.xsd#Organization" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/OrganizationDetails" xlink:href="csgp-20171231.xsd#OrganizationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/PropertyAndEquipment" xlink:href="csgp-20171231.xsd#PropertyAndEquipment" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/PropertyAndEquipmentDetails" xlink:href="csgp-20171231.xsd#PropertyAndEquipmentDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/PropertyAndEquipmentTables" xlink:href="csgp-20171231.xsd#PropertyAndEquipmentTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/QuarterlyResults" xlink:href="csgp-20171231.xsd#QuarterlyResults" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/QuarterlyResultsDetails" xlink:href="csgp-20171231.xsd#QuarterlyResultsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/QuarterlyResultsTables" xlink:href="csgp-20171231.xsd#QuarterlyResultsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/ScheduleIiValuationAndQualifyingAccounts" xlink:href="csgp-20171231.xsd#ScheduleIiValuationAndQualifyingAccounts" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/ScheduleIiValuationAndQualifyingAccountsDetails" xlink:href="csgp-20171231.xsd#ScheduleIiValuationAndQualifyingAccountsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SegmentReporting" xlink:href="csgp-20171231.xsd#SegmentReporting" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SegmentReportingAssetsAndLiabilitiesDetails" xlink:href="csgp-20171231.xsd#SegmentReportingAssetsAndLiabilitiesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SegmentReportingDetails" xlink:href="csgp-20171231.xsd#SegmentReportingDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SegmentReportingSegmentReportingRevenuesByServicesDetails" xlink:href="csgp-20171231.xsd#SegmentReportingSegmentReportingRevenuesByServicesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SegmentReportingTables" xlink:href="csgp-20171231.xsd#SegmentReportingTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/StockholdersEquity" xlink:href="csgp-20171231.xsd#StockholdersEquity" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/StockholdersEquityDetails" xlink:href="csgp-20171231.xsd#StockholdersEquityDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SubsequentEvents" xlink:href="csgp-20171231.xsd#SubsequentEvents" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SubsequentEventsDetails" xlink:href="csgp-20171231.xsd#SubsequentEventsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SummaryOfSignificantAccountingPolicies" xlink:href="csgp-20171231.xsd#SummaryOfSignificantAccountingPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesDetailsCashAndCashEquivalentsAndConcentrationOfCreditRisk" xlink:href="csgp-20171231.xsd#SummaryOfSignificantAccountingPoliciesDetailsCashAndCashEquivalentsAndConcentrationOfCreditRisk" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesDetailsDebtIssuanceCostsAndRecentAccountingPronouncements" xlink:href="csgp-20171231.xsd#SummaryOfSignificantAccountingPoliciesDetailsDebtIssuanceCostsAndRecentAccountingPronouncements" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesDetailsForeignCurrencyTranslationAndAccumulatedOtherComprehensiveLoss" xlink:href="csgp-20171231.xsd#SummaryOfSignificantAccountingPoliciesDetailsForeignCurrencyTranslationAndAccumulatedOtherComprehensiveLoss" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesDetailsGoodwillAndIntangibleAssets" xlink:href="csgp-20171231.xsd#SummaryOfSignificantAccountingPoliciesDetailsGoodwillAndIntangibleAssets" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesDetailsPropertyAndEquipment" xlink:href="csgp-20171231.xsd#SummaryOfSignificantAccountingPoliciesDetailsPropertyAndEquipment" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesDetailsRevenueRecognitionAndAdvertisingCosts" xlink:href="csgp-20171231.xsd#SummaryOfSignificantAccountingPoliciesDetailsRevenueRecognitionAndAdvertisingCosts" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesDetailsStockBasedCompensation" xlink:href="csgp-20171231.xsd#SummaryOfSignificantAccountingPoliciesDetailsStockBasedCompensation" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesPolicies" xlink:href="csgp-20171231.xsd#SummaryOfSignificantAccountingPoliciesPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesRecentAccountingPronouncementsDetails" xlink:href="csgp-20171231.xsd#SummaryOfSignificantAccountingPoliciesRecentAccountingPronouncementsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesTables" xlink:href="csgp-20171231.xsd#SummaryOfSignificantAccountingPoliciesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedNetLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedNetLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodEndLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodEndLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodStartLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodStartLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTerseLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTotalLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/netLabel" xlink:href="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd#netLabel" xlink:type="simple" />
  <link:presentationLink xlink:role="http://www.costar.com/role/Acquisition" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationsAbstract" xlink:label="loc_us-gaap_BusinessCombinationsAbstract_E6762B438DFD32149233DA91C5653F5D" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationDisclosureTextBlock" xlink:label="loc_us-gaap_BusinessCombinationDisclosureTextBlock_3F538ED009E6E367A1B1DA91C5669E71" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessCombinationsAbstract_E6762B438DFD32149233DA91C5653F5D" xlink:to="loc_us-gaap_BusinessCombinationDisclosureTextBlock_3F538ED009E6E367A1B1DA91C5669E71" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/AcquisitionAcquisitionDetailsScheduleOfAssetsAcquiredAndLiabilitiesAssumedForApartmentFinderDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationsAbstract" xlink:label="loc_us-gaap_BusinessCombinationsAbstract_5DFA7CBC92520ABCD6FBDA91C49E06AA" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_D3FD0D888F0B32BD9A9CDA91C49EF222" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessCombinationsAbstract_5DFA7CBC92520ABCD6FBDA91C49E06AA" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_D3FD0D888F0B32BD9A9CDA91C49EF222" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_2D9947DCCFC558FD3D29DA91C49E3A40" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_D3FD0D888F0B32BD9A9CDA91C49EF222" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_2D9947DCCFC558FD3D29DA91C49E3A40" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_022EC41FC353BCA92B46DA91C49FFEE4" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_2D9947DCCFC558FD3D29DA91C49E3A40" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_022EC41FC353BCA92B46DA91C49FFEE4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TradeNamesMember" xlink:label="loc_us-gaap_TradeNamesMember_F785A2786C24C75F0826DA91C49F323C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_022EC41FC353BCA92B46DA91C49FFEE4" xlink:to="loc_us-gaap_TradeNamesMember_F785A2786C24C75F0826DA91C49F323C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CustomerContractsMember" xlink:label="loc_us-gaap_CustomerContractsMember_2AD9340EAD3BD168BC33DA91C49F56E1" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_022EC41FC353BCA92B46DA91C49FFEE4" xlink:to="loc_us-gaap_CustomerContractsMember_2AD9340EAD3BD168BC33DA91C49F56E1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DevelopedTechnologyRightsMember" xlink:label="loc_us-gaap_DevelopedTechnologyRightsMember_2E8BA1A8C8DF92CDE414DA91C49F5554" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_022EC41FC353BCA92B46DA91C49FFEE4" xlink:to="loc_us-gaap_DevelopedTechnologyRightsMember_2E8BA1A8C8DF92CDE414DA91C49F5554" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_BuildingPhotographyMember" xlink:label="loc_csgp_BuildingPhotographyMember_CF57C2DFFB312B3AAD42DA91C49F4F38" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_022EC41FC353BCA92B46DA91C49FFEE4" xlink:to="loc_csgp_BuildingPhotographyMember_CF57C2DFFB312B3AAD42DA91C49F4F38" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_AE0CAB2B2484DD232138DA91C49F39BA" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_D3FD0D888F0B32BD9A9CDA91C49EF222" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_AE0CAB2B2484DD232138DA91C49F39BA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_C25C24BAE05DB7CB878DDA91C49F566A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_AE0CAB2B2484DD232138DA91C49F39BA" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_C25C24BAE05DB7CB878DDA91C49F566A" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_ApartmentFinderMember" xlink:label="loc_csgp_ApartmentFinderMember_CB363D017558AA00ACBCDA91C49F80DD" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_C25C24BAE05DB7CB878DDA91C49F566A" xlink:to="loc_csgp_ApartmentFinderMember_CB363D017558AA00ACBCDA91C49F80DD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_1668712A7E4A2F41368EDA91C49F17E9" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_D3FD0D888F0B32BD9A9CDA91C49EF222" xlink:to="loc_us-gaap_BusinessAcquisitionLineItems_1668712A7E4A2F41368EDA91C49F17E9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_6A46B35AF299AD1B9227DA91C49F6129" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_1668712A7E4A2F41368EDA91C49F17E9" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_6A46B35AF299AD1B9227DA91C49F6129" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_C868505655E70BBB1A0DDA91C49F8227" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_1668712A7E4A2F41368EDA91C49F17E9" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_C868505655E70BBB1A0DDA91C49F8227" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_C41C6ACF1F8807931DD2DA91C4A05A88" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_1668712A7E4A2F41368EDA91C49F17E9" xlink:to="loc_us-gaap_Goodwill_C41C6ACF1F8807931DD2DA91C4A05A88" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_B62CDC789C90C1FF6D2EDA91C4A010A7" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_1668712A7E4A2F41368EDA91C49F17E9" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_B62CDC789C90C1FF6D2EDA91C4A010A7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssets" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssets_E5AC26727BF5EEA1B544DA91C4A07CDB" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_1668712A7E4A2F41368EDA91C49F17E9" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssets_E5AC26727BF5EEA1B544DA91C4A07CDB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_5D1A02AC613A3C28E653DA91C4A0DE64" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_1668712A7E4A2F41368EDA91C49F17E9" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_5D1A02AC613A3C28E653DA91C4A0DE64" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_A2C5D06315E4D81F1DF1DA91C4A00EF9" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_1668712A7E4A2F41368EDA91C49F17E9" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_A2C5D06315E4D81F1DF1DA91C4A00EF9" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/AcquisitionDetailsForApartmentFinder" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationsAbstract" xlink:label="loc_us-gaap_BusinessCombinationsAbstract_3775368A83FBF230F62BDA91C4D1A28C" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_9F05C3FD40816C5DC20BDA91C4D19028" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessCombinationsAbstract_3775368A83FBF230F62BDA91C4D1A28C" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_9F05C3FD40816C5DC20BDA91C4D19028" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_3F92F1AC61ECACEF6723DA91C4D190E4" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_9F05C3FD40816C5DC20BDA91C4D19028" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_3F92F1AC61ECACEF6723DA91C4D190E4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_0CF361B3D34FCA729073DA91C4D17D93" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_3F92F1AC61ECACEF6723DA91C4D190E4" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_0CF361B3D34FCA729073DA91C4D17D93" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TradeNamesMember" xlink:label="loc_us-gaap_TradeNamesMember_8D9CFAEB27ADEAB70445DA91C4D1F979" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_0CF361B3D34FCA729073DA91C4D17D93" xlink:to="loc_us-gaap_TradeNamesMember_8D9CFAEB27ADEAB70445DA91C4D1F979" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CustomerContractsMember" xlink:label="loc_us-gaap_CustomerContractsMember_877BBBBAC9E31863834BDA91C4D11B4E" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_0CF361B3D34FCA729073DA91C4D17D93" xlink:to="loc_us-gaap_CustomerContractsMember_877BBBBAC9E31863834BDA91C4D11B4E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DevelopedTechnologyRightsMember" xlink:label="loc_us-gaap_DevelopedTechnologyRightsMember_BEAFBEC1BD66CB441FABDA91C4D16D42" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_0CF361B3D34FCA729073DA91C4D17D93" xlink:to="loc_us-gaap_DevelopedTechnologyRightsMember_BEAFBEC1BD66CB441FABDA91C4D16D42" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_BuildingPhotographyMember" xlink:label="loc_csgp_BuildingPhotographyMember_CCBAF0CE901A73E0EE16DA91C4D10511" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_0CF361B3D34FCA729073DA91C4D17D93" xlink:to="loc_csgp_BuildingPhotographyMember_CCBAF0CE901A73E0EE16DA91C4D10511" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_6E0322BA1F6095A1F6A2DA91C4D10990" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_9F05C3FD40816C5DC20BDA91C4D19028" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_6E0322BA1F6095A1F6A2DA91C4D10990" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_FFF9CABA4528D2202EE9DA91C4D19A77" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_6E0322BA1F6095A1F6A2DA91C4D10990" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_FFF9CABA4528D2202EE9DA91C4D19A77" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_ApartmentFinderMember" xlink:label="loc_csgp_ApartmentFinderMember_45AB65D3B5C1DD354101DA91C4D1F40C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_FFF9CABA4528D2202EE9DA91C4D19A77" xlink:to="loc_csgp_ApartmentFinderMember_45AB65D3B5C1DD354101DA91C4D1F40C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_74330E9ADB39661BD280DA91C4D29A1B" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_9F05C3FD40816C5DC20BDA91C4D19028" xlink:to="loc_us-gaap_BusinessAcquisitionLineItems_74330E9ADB39661BD280DA91C4D29A1B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired" xlink:label="loc_us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired_77F03F74350B7CF7DF27DA91C4D20273" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_74330E9ADB39661BD280DA91C4D29A1B" xlink:to="loc_us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired_77F03F74350B7CF7DF27DA91C4D20273" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentsToAcquireBusinessesGross" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesGross_57A627ADDACA1E9E0C0BDA91C4D24EFB" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_74330E9ADB39661BD280DA91C4D29A1B" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesGross_57A627ADDACA1E9E0C0BDA91C4D24EFB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentsForPreviousAcquisition" xlink:label="loc_us-gaap_PaymentsForPreviousAcquisition_B3229B6CD9085B9E24D9DA91C4D2D849" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_74330E9ADB39661BD280DA91C4D29A1B" xlink:to="loc_us-gaap_PaymentsForPreviousAcquisition_B3229B6CD9085B9E24D9DA91C4D2D849" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GoodwillPurchaseAccountingAdjustments" xlink:label="loc_us-gaap_GoodwillPurchaseAccountingAdjustments_EF1B419DFD6A26F6D998DA91C4D260D3" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_74330E9ADB39661BD280DA91C4D29A1B" xlink:to="loc_us-gaap_GoodwillPurchaseAccountingAdjustments_EF1B419DFD6A26F6D998DA91C4D260D3" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_NumberOfDistinctIntangibleAsset" xlink:label="loc_csgp_NumberOfDistinctIntangibleAsset_6F4A047804600D281BD3DA91C4D2EBD2" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_74330E9ADB39661BD280DA91C4D29A1B" xlink:to="loc_csgp_NumberOfDistinctIntangibleAsset_6F4A047804600D281BD3DA91C4D2EBD2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife" xlink:label="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_9BD82B6EE46CF8BC1125DA91C4D2792C" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_74330E9ADB39661BD280DA91C4D29A1B" xlink:to="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_9BD82B6EE46CF8BC1125DA91C4D2792C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_9BB570D3F52A2B29CBD2DA91C4D26357" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_74330E9ADB39661BD280DA91C4D29A1B" xlink:to="loc_us-gaap_Goodwill_9BB570D3F52A2B29CBD2DA91C4D26357" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount" xlink:label="loc_us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount_41852793F4AD789358D2DA91C4D2B6DD" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_74330E9ADB39661BD280DA91C4D29A1B" xlink:to="loc_us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount_41852793F4AD789358D2DA91C4D2B6DD" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/AcquisitionPolicies" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationsAbstract" xlink:label="loc_us-gaap_BusinessCombinationsAbstract_C056923892D1B1CB2672DA91C514DD51" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_57E6DD6930308735D703DA91C5144921" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessCombinationsAbstract_C056923892D1B1CB2672DA91C514DD51" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_57E6DD6930308735D703DA91C5144921" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_125405CC9A4CE8368F2FDA91C5150109" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_57E6DD6930308735D703DA91C5144921" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_125405CC9A4CE8368F2FDA91C5150109" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_AB7CD9B28E020D7CEA24DA91C5152B0B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_125405CC9A4CE8368F2FDA91C5150109" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_AB7CD9B28E020D7CEA24DA91C5152B0B" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_ApartmentFinderMember" xlink:label="loc_csgp_ApartmentFinderMember_2913680A0DD42A38A85ADA91C515F9C8" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_AB7CD9B28E020D7CEA24DA91C5152B0B" xlink:to="loc_csgp_ApartmentFinderMember_2913680A0DD42A38A85ADA91C515F9C8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_CDEC41B1685B98193379DA91C5154C3A" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_57E6DD6930308735D703DA91C5144921" xlink:to="loc_us-gaap_BusinessAcquisitionLineItems_CDEC41B1685B98193379DA91C5154C3A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationsPolicy" xlink:label="loc_us-gaap_BusinessCombinationsPolicy_9C3A306E470C968EE1BDDA91C51555FA" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_CDEC41B1685B98193379DA91C5154C3A" xlink:to="loc_us-gaap_BusinessCombinationsPolicy_9C3A306E470C968EE1BDDA91C51555FA" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/AcquisitionTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationsAbstract" xlink:label="loc_us-gaap_BusinessCombinationsAbstract_C05A717724A8BF4E7DC9DA91C5399C3D" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_C6BC0E051073DD191B28DA91C539A8A0" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessCombinationsAbstract_C05A717724A8BF4E7DC9DA91C5399C3D" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_C6BC0E051073DD191B28DA91C539A8A0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_D0B77C2BE41F78C94389DA91C5397650" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_C6BC0E051073DD191B28DA91C539A8A0" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_D0B77C2BE41F78C94389DA91C5397650" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_1D21C06EAAF70906B19CDA91C5391689" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_D0B77C2BE41F78C94389DA91C5397650" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_1D21C06EAAF70906B19CDA91C5391689" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_ApartmentFinderMember" xlink:label="loc_csgp_ApartmentFinderMember_BB3533EE3D98D77799E9DA91C53A50B2" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_1D21C06EAAF70906B19CDA91C5391689" xlink:to="loc_csgp_ApartmentFinderMember_BB3533EE3D98D77799E9DA91C53A50B2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_3162015B06E85DC7B0ABDA91C53AD77D" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_C6BC0E051073DD191B28DA91C539A8A0" xlink:to="loc_us-gaap_BusinessAcquisitionLineItems_3162015B06E85DC7B0ABDA91C53AD77D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock_77DF88130C87A3288CA1DA91C53AA21D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_3162015B06E85DC7B0ABDA91C53AD77D" xlink:to="loc_us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock_77DF88130C87A3288CA1DA91C53AA21D" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/CommitmentsAndContingencies" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_E1A61CFA18A35216547ADA91C50AD2C9" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_9ED4CDD94A88759E9C61DA91C50B9EE8" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_E1A61CFA18A35216547ADA91C50AD2C9" xlink:to="loc_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_9ED4CDD94A88759E9C61DA91C50B9EE8" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/CommitmentsAndContingenciesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_FEE22FBD681EA7494A15BAB943A2A0CA" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLeasesRentExpenseAbstract" xlink:label="loc_us-gaap_OperatingLeasesRentExpenseAbstract_93D9B2E797E6F7AAFBEEBAB943A22591" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_FEE22FBD681EA7494A15BAB943A2A0CA" xlink:to="loc_us-gaap_OperatingLeasesRentExpenseAbstract_93D9B2E797E6F7AAFBEEBAB943A22591" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLeasesRentExpenseNet" xlink:label="loc_us-gaap_OperatingLeasesRentExpenseNet_F39CA11AAC3B4E627CD6BAB943A2BAD0" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLeasesRentExpenseAbstract_93D9B2E797E6F7AAFBEEBAB943A22591" xlink:to="loc_us-gaap_OperatingLeasesRentExpenseNet_F39CA11AAC3B4E627CD6BAB943A2BAD0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_165C1104B28B85F29592BAB943A23949" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_FEE22FBD681EA7494A15BAB943A2A0CA" xlink:to="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_165C1104B28B85F29592BAB943A23949" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_7B69D5CBCD10474DAE7FBAB943A3C1DD" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_165C1104B28B85F29592BAB943A23949" xlink:to="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_7B69D5CBCD10474DAE7FBAB943A3C1DD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_40C742EAE201602AC04ABAB943A3796D" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_165C1104B28B85F29592BAB943A23949" xlink:to="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_40C742EAE201602AC04ABAB943A3796D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_3130801FE50FBC2046A4BAB943A37E3B" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_165C1104B28B85F29592BAB943A23949" xlink:to="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_3130801FE50FBC2046A4BAB943A37E3B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_A114616F06262CCE95EBBAB943A3B744" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_165C1104B28B85F29592BAB943A23949" xlink:to="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_A114616F06262CCE95EBBAB943A3B744" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears_032B1724C29282755942BAB943A34EE9" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_165C1104B28B85F29592BAB943A23949" xlink:to="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears_032B1724C29282755942BAB943A34EE9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter_1649B47434232E7E0EB9BAB943A3E8E8" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_165C1104B28B85F29592BAB943A23949" xlink:to="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter_1649B47434232E7E0EB9BAB943A3E8E8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDue" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDue_85D1E49F93D8FD5B9A0BBAB943A36FB8" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueAbstract_165C1104B28B85F29592BAB943A23949" xlink:to="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDue_85D1E49F93D8FD5B9A0BBAB943A36FB8" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/CommitmentsAndContingenciesPolicies" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_8A5FC6918E9444508AB8DA91C4585F1A" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LiabilityReserveEstimatePolicy" xlink:label="loc_us-gaap_LiabilityReserveEstimatePolicy_A8BFB2353E7D6392C5C7DA91C4585883" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_8A5FC6918E9444508AB8DA91C4585F1A" xlink:to="loc_us-gaap_LiabilityReserveEstimatePolicy_A8BFB2353E7D6392C5C7DA91C4585883" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/CommitmentsAndContingenciesTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_B49847228FA94AA229FADA91C4FA329D" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock_93E8D9AEA6252876D036DA91C4FA19FA" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_B49847228FA94AA229FADA91C4FA329D" xlink:to="loc_us-gaap_ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock_93E8D9AEA6252876D036DA91C4FA19FA" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/ConsolidatedBalanceSheets" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementOfFinancialPositionAbstract" xlink:label="loc_us-gaap_StatementOfFinancialPositionAbstract_D0632C20F6A5959A03E1BAB92CFA1905" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AssetsAbstract" xlink:label="loc_us-gaap_AssetsAbstract_69C8CDD9EA68C4194EF7BAB92CFAAFDC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_D0632C20F6A5959A03E1BAB92CFA1905" xlink:to="loc_us-gaap_AssetsAbstract_69C8CDD9EA68C4194EF7BAB92CFAAFDC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AssetsCurrentAbstract" xlink:label="loc_us-gaap_AssetsCurrentAbstract_80350453BA0D0DC78D4ABAB92CFCDD5C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsAbstract_69C8CDD9EA68C4194EF7BAB92CFAAFDC" xlink:to="loc_us-gaap_AssetsCurrentAbstract_80350453BA0D0DC78D4ABAB92CFCDD5C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_ABCFA5698EDD65F673D5BAB92CFCA52F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsCurrentAbstract_80350453BA0D0DC78D4ABAB92CFCDD5C" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_ABCFA5698EDD65F673D5BAB92CFCA52F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_562C7A140FED5C4E0585BAB92CFCBB05" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsCurrentAbstract_80350453BA0D0DC78D4ABAB92CFCDD5C" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_562C7A140FED5C4E0585BAB92CFCBB05" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxesReceivable" xlink:label="loc_us-gaap_IncomeTaxesReceivable_FF59A04C9B8C2DC883A6BAB92CFCF129" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsCurrentAbstract_80350453BA0D0DC78D4ABAB92CFCDD5C" xlink:to="loc_us-gaap_IncomeTaxesReceivable_FF59A04C9B8C2DC883A6BAB92CFCF129" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_96DDDFE3EBD5D77B0CB4BAB92CFC2868" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsCurrentAbstract_80350453BA0D0DC78D4ABAB92CFCDD5C" xlink:to="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_96DDDFE3EBD5D77B0CB4BAB92CFC2868" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AssetsCurrent" xlink:label="loc_us-gaap_AssetsCurrent_68C135E32DA76AEDFA40BAB92CFD0E8E" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsCurrentAbstract_80350453BA0D0DC78D4ABAB92CFCDD5C" xlink:to="loc_us-gaap_AssetsCurrent_68C135E32DA76AEDFA40BAB92CFD0E8E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermInvestments" xlink:label="loc_us-gaap_LongTermInvestments_1935B32E6C278A0E39B5BAB92CFD32F3" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsAbstract_69C8CDD9EA68C4194EF7BAB92CFAAFDC" xlink:to="loc_us-gaap_LongTermInvestments_1935B32E6C278A0E39B5BAB92CFD32F3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredIncomeTaxAssetsNet" xlink:label="loc_us-gaap_DeferredIncomeTaxAssetsNet_54ECDE04ED629A6E3426BAB92CFDB1A7" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsAbstract_69C8CDD9EA68C4194EF7BAB92CFAAFDC" xlink:to="loc_us-gaap_DeferredIncomeTaxAssetsNet_54ECDE04ED629A6E3426BAB92CFDB1A7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_C82FD5A218DF07C51D25BAB92CFD2BFF" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsAbstract_69C8CDD9EA68C4194EF7BAB92CFAAFDC" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_C82FD5A218DF07C51D25BAB92CFD2BFF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_BEA32BD780FE34F30B82BAB92CFD6B7F" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsAbstract_69C8CDD9EA68C4194EF7BAB92CFAAFDC" xlink:to="loc_us-gaap_Goodwill_BEA32BD780FE34F30B82BAB92CFD6B7F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_1D04243C2FEE9DC86BE8BAB92CFDB616" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsAbstract_69C8CDD9EA68C4194EF7BAB92CFAAFDC" xlink:to="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_1D04243C2FEE9DC86BE8BAB92CFDB616" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DepositsAssetsNoncurrent" xlink:label="loc_us-gaap_DepositsAssetsNoncurrent_5B3EC6CD48C0B3E6C04ABAB92CFD3BF3" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsAbstract_69C8CDD9EA68C4194EF7BAB92CFAAFDC" xlink:to="loc_us-gaap_DepositsAssetsNoncurrent_5B3EC6CD48C0B3E6C04ABAB92CFD3BF3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxesReceivableNoncurrent" xlink:label="loc_us-gaap_IncomeTaxesReceivableNoncurrent_270CE91DA9FA186184C1BAB92CFD2ECE" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsAbstract_69C8CDD9EA68C4194EF7BAB92CFAAFDC" xlink:to="loc_us-gaap_IncomeTaxesReceivableNoncurrent_270CE91DA9FA186184C1BAB92CFD2ECE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Assets" xlink:label="loc_us-gaap_Assets_D518445048B910688496BAB92CFDDA22" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsAbstract_69C8CDD9EA68C4194EF7BAB92CFAAFDC" xlink:to="loc_us-gaap_Assets_D518445048B910688496BAB92CFDDA22" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_EEE7053DE89B131B048CBAB92CFD9C68" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_D0632C20F6A5959A03E1BAB92CFA1905" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_EEE7053DE89B131B048CBAB92CFD9C68" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LiabilitiesCurrentAbstract" xlink:label="loc_us-gaap_LiabilitiesCurrentAbstract_17DF8AC3B90F23C750CBBAB92CFD0C6B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_EEE7053DE89B131B048CBAB92CFD9C68" xlink:to="loc_us-gaap_LiabilitiesCurrentAbstract_17DF8AC3B90F23C750CBBAB92CFD0C6B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtCurrent" xlink:label="loc_us-gaap_LongTermDebtCurrent_083DD4C90517543AF114BAB92CFD682D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_17DF8AC3B90F23C750CBBAB92CFD0C6B" xlink:to="loc_us-gaap_LongTermDebtCurrent_083DD4C90517543AF114BAB92CFD682D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaap_AccountsPayableCurrent_B72D29F738F21054463BBAB92CFDB1DF" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_17DF8AC3B90F23C750CBBAB92CFD0C6B" xlink:to="loc_us-gaap_AccountsPayableCurrent_B72D29F738F21054463BBAB92CFDB1DF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EmployeeRelatedLiabilitiesCurrent" xlink:label="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_D1971BF09D817C493764BAB92CFD3F22" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_17DF8AC3B90F23C750CBBAB92CFD0C6B" xlink:to="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_D1971BF09D817C493764BAB92CFD3F22" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccruedLiabilitiesCurrent" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent_13B9DA579814CD85400BBAB92CFD2BE7" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_17DF8AC3B90F23C750CBBAB92CFD0C6B" xlink:to="loc_us-gaap_AccruedLiabilitiesCurrent_13B9DA579814CD85400BBAB92CFD2BE7" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_Deferredgainonthesaleofbuildingcurrent" xlink:label="loc_csgp_Deferredgainonthesaleofbuildingcurrent_B95E28F3BCFE67C8D097BAB92CFDA576" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_17DF8AC3B90F23C750CBBAB92CFD0C6B" xlink:to="loc_csgp_Deferredgainonthesaleofbuildingcurrent_B95E28F3BCFE67C8D097BAB92CFDA576" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccruedIncomeTaxesCurrent" xlink:label="loc_us-gaap_AccruedIncomeTaxesCurrent_7284EE615EED2AFB634BBAB92CFD41F7" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_17DF8AC3B90F23C750CBBAB92CFD0C6B" xlink:to="loc_us-gaap_AccruedIncomeTaxesCurrent_7284EE615EED2AFB634BBAB92CFD41F7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredRentCreditCurrent" xlink:label="loc_us-gaap_DeferredRentCreditCurrent_22981DB4BDFF02E81AC8BAB92CFEDC32" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_17DF8AC3B90F23C750CBBAB92CFD0C6B" xlink:to="loc_us-gaap_DeferredRentCreditCurrent_22981DB4BDFF02E81AC8BAB92CFEDC32" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredRevenueCurrent" xlink:label="loc_us-gaap_DeferredRevenueCurrent_04C3B2E4D65A0CE7B0E1BAB92CFE8F8E" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_17DF8AC3B90F23C750CBBAB92CFD0C6B" xlink:to="loc_us-gaap_DeferredRevenueCurrent_04C3B2E4D65A0CE7B0E1BAB92CFE8F8E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaap_LiabilitiesCurrent_13E7B29CC55ACE9755E3BAB92CFE947F" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_17DF8AC3B90F23C750CBBAB92CFD0C6B" xlink:to="loc_us-gaap_LiabilitiesCurrent_13E7B29CC55ACE9755E3BAB92CFE947F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_7745C64F32E7EDF69E42BAB92CFE0ADC" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_EEE7053DE89B131B048CBAB92CFD9C68" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_7745C64F32E7EDF69E42BAB92CFE0ADC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredGainOnSaleOfProperty" xlink:label="loc_us-gaap_DeferredGainOnSaleOfProperty_51703E3B28262CECF869BAB92CFE69E4" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_EEE7053DE89B131B048CBAB92CFD9C68" xlink:to="loc_us-gaap_DeferredGainOnSaleOfProperty_51703E3B28262CECF869BAB92CFE69E4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredRentCreditNoncurrent" xlink:label="loc_us-gaap_DeferredRentCreditNoncurrent_99788FC50A458CB33C3ABAB92CFEA72A" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_EEE7053DE89B131B048CBAB92CFD9C68" xlink:to="loc_us-gaap_DeferredRentCreditNoncurrent_99788FC50A458CB33C3ABAB92CFEA72A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredIncomeTaxLiabilitiesNet" xlink:label="loc_us-gaap_DeferredIncomeTaxLiabilitiesNet_42E6F0EDBA444E685E3ABAB92CFE7BCC" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_EEE7053DE89B131B048CBAB92CFD9C68" xlink:to="loc_us-gaap_DeferredIncomeTaxLiabilitiesNet_42E6F0EDBA444E685E3ABAB92CFE7BCC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccruedIncomeTaxesNoncurrent" xlink:label="loc_us-gaap_AccruedIncomeTaxesNoncurrent_438A4B104A478282FB55BAB92CFE6948" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_EEE7053DE89B131B048CBAB92CFD9C68" xlink:to="loc_us-gaap_AccruedIncomeTaxesNoncurrent_438A4B104A478282FB55BAB92CFE6948" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaap_Liabilities_BE761DE29B304B6B70E9BAB92CFE9CDF" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_EEE7053DE89B131B048CBAB92CFD9C68" xlink:to="loc_us-gaap_Liabilities_BE761DE29B304B6B70E9BAB92CFE9CDF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommitmentsAndContingencies" xlink:label="loc_us-gaap_CommitmentsAndContingencies_F7D60C9E917E9C03BAD1BAB92CFE337E" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_EEE7053DE89B131B048CBAB92CFD9C68" xlink:to="loc_us-gaap_CommitmentsAndContingencies_F7D60C9E917E9C03BAD1BAB92CFE337E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_9BDB88F624DDF3CB6078BAB92CFE65A2" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_EEE7053DE89B131B048CBAB92CFD9C68" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_9BDB88F624DDF3CB6078BAB92CFE65A2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PreferredStockValue" xlink:label="loc_us-gaap_PreferredStockValue_18DA3F5622B18638A3EABAB92CFE7964" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_9BDB88F624DDF3CB6078BAB92CFE65A2" xlink:to="loc_us-gaap_PreferredStockValue_18DA3F5622B18638A3EABAB92CFE7964" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaap_CommonStockValue_9E1CE884BEA93596933EBAB92CFEF55A" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_9BDB88F624DDF3CB6078BAB92CFE65A2" xlink:to="loc_us-gaap_CommonStockValue_9E1CE884BEA93596933EBAB92CFEF55A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="loc_us-gaap_AdditionalPaidInCapital_CA49E618BC14F9DAB48FBAB92CFE1273" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_9BDB88F624DDF3CB6078BAB92CFE65A2" xlink:to="loc_us-gaap_AdditionalPaidInCapital_CA49E618BC14F9DAB48FBAB92CFE1273" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_B8FB269666BBF4713CE0BAB92CFEAE2B" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_9BDB88F624DDF3CB6078BAB92CFE65A2" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_B8FB269666BBF4713CE0BAB92CFEAE2B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_279908C3EEDCBA75683EBAB92CFF970B" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_9BDB88F624DDF3CB6078BAB92CFE65A2" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_279908C3EEDCBA75683EBAB92CFF970B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaap_StockholdersEquity_FB9BE56C1728B61DABB7BAB92CFFFF9B" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_9BDB88F624DDF3CB6078BAB92CFE65A2" xlink:to="loc_us-gaap_StockholdersEquity_FB9BE56C1728B61DABB7BAB92CFFFF9B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_25190B1231649EB9FFC3BAB92CFF6D01" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_EEE7053DE89B131B048CBAB92CFD9C68" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquity_25190B1231649EB9FFC3BAB92CFF6D01" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/ConsolidatedBalanceSheetsParenthetical" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementOfFinancialPositionAbstract" xlink:label="loc_us-gaap_StatementOfFinancialPositionAbstract_66D940E934EFFC06A00FDA91C3B7664E" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable_F5D8E237C69257063785DA91C3B78890" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_66D940E934EFFC06A00FDA91C3B7664E" xlink:to="loc_us-gaap_StatementTable_F5D8E237C69257063785DA91C3B78890" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementScenarioAxis" xlink:label="loc_us-gaap_StatementScenarioAxis_3BDD46BD6005D6BF134EDA91C3B76CA9" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementTable_F5D8E237C69257063785DA91C3B78890" xlink:to="loc_us-gaap_StatementScenarioAxis_3BDD46BD6005D6BF134EDA91C3B76CA9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_1F2814BBABC12AF6CCDEDA91C3B78EAD" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementScenarioAxis_3BDD46BD6005D6BF134EDA91C3B76CA9" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_1F2814BBABC12AF6CCDEDA91C3B78EAD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaap_StatementLineItems_1B782C86710BBDA918D4DA91C3B8C864" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementTable_F5D8E237C69257063785DA91C3B78890" xlink:to="loc_us-gaap_StatementLineItems_1B782C86710BBDA918D4DA91C3B8C864" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent" xlink:label="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_B44311E1D02A2DA32C3DDA91C3B8D429" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_1B782C86710BBDA918D4DA91C3B8C864" xlink:to="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_B44311E1D02A2DA32C3DDA91C3B8D429" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PreferredStockParOrStatedValuePerShare" xlink:label="loc_us-gaap_PreferredStockParOrStatedValuePerShare_FDB68D4B54AE086BB715DA91C3B83A94" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_1B782C86710BBDA918D4DA91C3B8C864" xlink:to="loc_us-gaap_PreferredStockParOrStatedValuePerShare_FDB68D4B54AE086BB715DA91C3B83A94" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized_6906549EFBB82D8DD121DA91C3B8DE29" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_1B782C86710BBDA918D4DA91C3B8C864" xlink:to="loc_us-gaap_PreferredStockSharesAuthorized_6906549EFBB82D8DD121DA91C3B8DE29" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PreferredStockSharesOutstanding" xlink:label="loc_us-gaap_PreferredStockSharesOutstanding_78DFF893251261FD2C6ADA91C3B8E313" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_1B782C86710BBDA918D4DA91C3B8C864" xlink:to="loc_us-gaap_PreferredStockSharesOutstanding_78DFF893251261FD2C6ADA91C3B8E313" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_B5CAEFD4ADB205F90340DA91C3B81B08" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_1B782C86710BBDA918D4DA91C3B8C864" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_B5CAEFD4ADB205F90340DA91C3B81B08" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_EC2ECBEB6FA9D04F4F12DA91C3B8C08B" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_1B782C86710BBDA918D4DA91C3B8C864" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_EC2ECBEB6FA9D04F4F12DA91C3B8C08B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommonStockSharesIssued" xlink:label="loc_us-gaap_CommonStockSharesIssued_B33F9FDF5DACD5EBDF54DA91C3B8FCE2" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_1B782C86710BBDA918D4DA91C3B8C864" xlink:to="loc_us-gaap_CommonStockSharesIssued_B33F9FDF5DACD5EBDF54DA91C3B8FCE2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_8A25E63C361182A8E771DA91C3B8BE53" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_1B782C86710BBDA918D4DA91C3B8C864" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_8A25E63C361182A8E771DA91C3B8BE53" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/ConsolidatedStatementsOfCashFlows" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementOfCashFlowsAbstract" xlink:label="loc_us-gaap_StatementOfCashFlowsAbstract_4FBC5014D27D70AD2A10BDDBE07C33CC" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_331CA78F510AAAA993E9BDDBE07C7777" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_4FBC5014D27D70AD2A10BDDBE07C33CC" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_331CA78F510AAAA993E9BDDBE07C7777" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_2625EA5F960C9CC863F5BDDBE07CB73F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_331CA78F510AAAA993E9BDDBE07C7777" xlink:to="loc_us-gaap_NetIncomeLoss_2625EA5F960C9CC863F5BDDBE07CB73F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_5F301CCD6F90EE5B2116BDDBE07D5847" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_331CA78F510AAAA993E9BDDBE07C7777" xlink:to="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_5F301CCD6F90EE5B2116BDDBE07D5847" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DepreciationDepletionAndAmortization" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_3190EBA452AF12320D9EBDDBE07DECC6" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_5F301CCD6F90EE5B2116BDDBE07D5847" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_3190EBA452AF12320D9EBDDBE07DECC6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AmortizationOfFinancingCostsAndDiscounts" xlink:label="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_DAAB14A7AB9E1E072C94BDDBE07E7835" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_5F301CCD6F90EE5B2116BDDBE07D5847" xlink:to="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_DAAB14A7AB9E1E072C94BDDBE07E7835" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_FEC2AD512F528763A330BDDBE07EF651" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_5F301CCD6F90EE5B2116BDDBE07D5847" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_FEC2AD512F528763A330BDDBE07EF651" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ImpairmentOfIntangibleAssetsFinitelived" xlink:label="loc_us-gaap_ImpairmentOfIntangibleAssetsFinitelived_8650A9F90B0ADA819333BDDBE07EEEB6" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_5F301CCD6F90EE5B2116BDDBE07D5847" xlink:to="loc_us-gaap_ImpairmentOfIntangibleAssetsFinitelived_8650A9F90B0ADA819333BDDBE07EEEB6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown" xlink:label="loc_us-gaap_DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown_95C8976E94EDFB17836CBDDBE07E2F40" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_5F301CCD6F90EE5B2116BDDBE07D5847" xlink:to="loc_us-gaap_DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown_95C8976E94EDFB17836CBDDBE07E2F40" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GainLossOnInvestmentsExcludingOtherThanTemporaryImpairments" xlink:label="loc_us-gaap_GainLossOnInvestmentsExcludingOtherThanTemporaryImpairments_C9D671F29DE2FC9D1F67BDDBE07E1CB5" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_5F301CCD6F90EE5B2116BDDBE07D5847" xlink:to="loc_us-gaap_GainLossOnInvestmentsExcludingOtherThanTemporaryImpairments_C9D671F29DE2FC9D1F67BDDBE07E1CB5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensation" xlink:label="loc_us-gaap_ShareBasedCompensation_0C0616EFBA5FCE6046F9BDDBE07E8EC9" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_5F301CCD6F90EE5B2116BDDBE07D5847" xlink:to="loc_us-gaap_ShareBasedCompensation_0C0616EFBA5FCE6046F9BDDBE07E8EC9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_9346628F37E49F532160BDDBE07E6C75" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_5F301CCD6F90EE5B2116BDDBE07D5847" xlink:to="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_9346628F37E49F532160BDDBE07E6C75" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProvisionForDoubtfulAccounts" xlink:label="loc_us-gaap_ProvisionForDoubtfulAccounts_0C3A1F49E4636F7D03FABDDBE07FF84D" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_5F301CCD6F90EE5B2116BDDBE07D5847" xlink:to="loc_us-gaap_ProvisionForDoubtfulAccounts_0C3A1F49E4636F7D03FABDDBE07FF84D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:label="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_2C14C5E13A6C71B9BEC2BDDBE07FBC40" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_331CA78F510AAAA993E9BDDBE07C7777" xlink:to="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_2C14C5E13A6C71B9BEC2BDDBE07FBC40" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_34D40BD0F848A6D93657BDDBE07F2C92" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_2C14C5E13A6C71B9BEC2BDDBE07FBC40" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_34D40BD0F848A6D93657BDDBE07F2C92" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable" xlink:label="loc_us-gaap_IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable_202515C350BA2842972FBDDBE07F1AE9" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_2C14C5E13A6C71B9BEC2BDDBE07FBC40" xlink:to="loc_us-gaap_IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable_202515C350BA2842972FBDDBE07F1AE9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:label="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_93E615A84B7AC5F29BD7BDDBE07F83D9" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_2C14C5E13A6C71B9BEC2BDDBE07FBC40" xlink:to="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_93E615A84B7AC5F29BD7BDDBE07F83D9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInIncomeTaxesReceivable" xlink:label="loc_us-gaap_IncreaseDecreaseInIncomeTaxesReceivable_E55FE6678FE70C5C4F53BDDBE080355D" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_2C14C5E13A6C71B9BEC2BDDBE07FBC40" xlink:to="loc_us-gaap_IncreaseDecreaseInIncomeTaxesReceivable_E55FE6678FE70C5C4F53BDDBE080355D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInDeposits" xlink:label="loc_us-gaap_IncreaseDecreaseInDeposits_3F82B662BD7011D56884BDDBE080942C" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_2C14C5E13A6C71B9BEC2BDDBE07FBC40" xlink:to="loc_us-gaap_IncreaseDecreaseInDeposits_3F82B662BD7011D56884BDDBE080942C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_B0F2F8F1149DBA5C6F61BDDBE08107AB" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_2C14C5E13A6C71B9BEC2BDDBE07FBC40" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_B0F2F8F1149DBA5C6F61BDDBE08107AB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInDeferredRevenue" xlink:label="loc_us-gaap_IncreaseDecreaseInDeferredRevenue_4585ADA9CC3D170246F9BDDBE081B3E4" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_2C14C5E13A6C71B9BEC2BDDBE07FBC40" xlink:to="loc_us-gaap_IncreaseDecreaseInDeferredRevenue_4585ADA9CC3D170246F9BDDBE081B3E4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_4A8E11F3FFD47D28F2EABDDBE0816A4F" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_331CA78F510AAAA993E9BDDBE07C7777" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_4A8E11F3FFD47D28F2EABDDBE0816A4F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_F192276FED69ACFAFD2CBDDBE081468A" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_4FBC5014D27D70AD2A10BDDBE07C33CC" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_F192276FED69ACFAFD2CBDDBE081468A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments" xlink:label="loc_us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments_E807F69D4951BCE1B964BDDBE08101ED" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_F192276FED69ACFAFD2CBDDBE081468A" xlink:to="loc_us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments_E807F69D4951BCE1B964BDDBE08101ED" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentsToAcquireProductiveAssets" xlink:label="loc_us-gaap_PaymentsToAcquireProductiveAssets_3D621406C8FE6E044923BDDBE08141E5" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_F192276FED69ACFAFD2CBDDBE081468A" xlink:to="loc_us-gaap_PaymentsToAcquireProductiveAssets_3D621406C8FE6E044923BDDBE08141E5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_63FA477D8D7C2E2BD76EBDDBE08128AB" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_F192276FED69ACFAFD2CBDDBE081468A" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_63FA477D8D7C2E2BD76EBDDBE08128AB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_3ED79FE30312014FECC3BDDBE082D11C" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_F192276FED69ACFAFD2CBDDBE081468A" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_3ED79FE30312014FECC3BDDBE082D11C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_7311A0974FC92144E267BDDBE08225CB" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_4FBC5014D27D70AD2A10BDDBE07C33CC" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_7311A0974FC92144E267BDDBE08225CB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RepaymentsOfLongTermDebt" xlink:label="loc_us-gaap_RepaymentsOfLongTermDebt_191234C2A5E0E150B86ABDDBE0822F41" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_7311A0974FC92144E267BDDBE08225CB" xlink:to="loc_us-gaap_RepaymentsOfLongTermDebt_191234C2A5E0E150B86ABDDBE0822F41" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentsOfDebtIssuanceCosts" xlink:label="loc_us-gaap_PaymentsOfDebtIssuanceCosts_A8ACA1BB11DE1C7DC428BDDBE0821C91" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_7311A0974FC92144E267BDDBE08225CB" xlink:to="loc_us-gaap_PaymentsOfDebtIssuanceCosts_A8ACA1BB11DE1C7DC428BDDBE0821C91" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation" xlink:label="loc_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_E22F6586939952C7F231BDDBE083B6BD" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_7311A0974FC92144E267BDDBE08225CB" xlink:to="loc_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_E22F6586939952C7F231BDDBE083B6BD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_C6D84E5B998D438E72C4BDDBE083168E" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_7311A0974FC92144E267BDDBE08225CB" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_C6D84E5B998D438E72C4BDDBE083168E" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_ProceedsFromExerciseOfStockOptionsAndEspp" xlink:label="loc_csgp_ProceedsFromExerciseOfStockOptionsAndEspp_46629153A45AD48FA2C4BDDBE0847159" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_7311A0974FC92144E267BDDBE08225CB" xlink:to="loc_csgp_ProceedsFromExerciseOfStockOptionsAndEspp_46629153A45AD48FA2C4BDDBE0847159" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_586815AFACC700216E46BDDBE0849EAD" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_7311A0974FC92144E267BDDBE08225CB" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_586815AFACC700216E46BDDBE0849EAD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents" xlink:label="loc_us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents_402780DF5B1008095388BDDBE08465FD" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_4FBC5014D27D70AD2A10BDDBE07C33CC" xlink:to="loc_us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents_402780DF5B1008095388BDDBE08465FD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease" xlink:label="loc_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_320AB87968F63CEA1333BDDBE0843DCE" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_4FBC5014D27D70AD2A10BDDBE07C33CC" xlink:to="loc_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_320AB87968F63CEA1333BDDBE0843DCE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_95C8D9C0AD5787E153BCBDDBE084D163" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_4FBC5014D27D70AD2A10BDDBE07C33CC" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_95C8D9C0AD5787E153BCBDDBE084D163" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_20349544C7889918DE68BDDBE084B764" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_4FBC5014D27D70AD2A10BDDBE07C33CC" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_20349544C7889918DE68BDDBE084B764" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/ConsolidatedStatementsOfComprehensiveIncomeLoss" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:label="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_B36126ED6BDAB7DB2A83AFECBD1FFA9F" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_FEED15E569C507EBA917AFECBD1F8B9C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_B36126ED6BDAB7DB2A83AFECBD1FFA9F" xlink:to="loc_us-gaap_NetIncomeLoss_FEED15E569C507EBA917AFECBD1F8B9C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_A6D836F1A8A2A29C0FAAAFECBD1F67F7" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_B36126ED6BDAB7DB2A83AFECBD1FFA9F" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_A6D836F1A8A2A29C0FAAAFECBD1F67F7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_C14EF78E2A92FAF09171AFECBD1F526D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_A6D836F1A8A2A29C0FAAAFECBD1F67F7" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_C14EF78E2A92FAF09171AFECBD1F526D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_5F31CFD0391FB81F16F8AFECBD1F67FD" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_A6D836F1A8A2A29C0FAAAFECBD1F67F7" xlink:to="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_5F31CFD0391FB81F16F8AFECBD1F67FD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax_4F9056FF826497E2771BAFECBD1FCB23" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_A6D836F1A8A2A29C0FAAAFECBD1F67F7" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax_4F9056FF826497E2771BAFECBD1FCB23" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_FB0F677EC6B6A3AFF136AFECBD1FC915" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_B36126ED6BDAB7DB2A83AFECBD1FFA9F" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_FB0F677EC6B6A3AFF136AFECBD1FC915" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTax" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax_9A07C3ACB289D90BFFBAAFECBD1F4907" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_B36126ED6BDAB7DB2A83AFECBD1FFA9F" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTax_9A07C3ACB289D90BFFBAAFECBD1F4907" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/ConsolidatedStatementsOfOperations" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementAbstract" xlink:label="loc_us-gaap_IncomeStatementAbstract_BF3660C5EA74D7CB7781BAB9451F6ED4" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_F42CDAAF563A4573A0E4BAB9451FC23A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementAbstract_BF3660C5EA74D7CB7781BAB9451F6ED4" xlink:to="loc_us-gaap_Revenues_F42CDAAF563A4573A0E4BAB9451FC23A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CostOfRevenue" xlink:label="loc_us-gaap_CostOfRevenue_DF7043C4D8A1D1321A45BAB9451F9122" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementAbstract_BF3660C5EA74D7CB7781BAB9451F6ED4" xlink:to="loc_us-gaap_CostOfRevenue_DF7043C4D8A1D1321A45BAB9451F9122" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GrossProfit" xlink:label="loc_us-gaap_GrossProfit_84596F9475388BC880A4BAB9451F5265" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementAbstract_BF3660C5EA74D7CB7781BAB9451F6ED4" xlink:to="loc_us-gaap_GrossProfit_84596F9475388BC880A4BAB9451F5265" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingExpensesAbstract" xlink:label="loc_us-gaap_OperatingExpensesAbstract_523A50968335A7669A46BAB9451F344C" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementAbstract_BF3660C5EA74D7CB7781BAB9451F6ED4" xlink:to="loc_us-gaap_OperatingExpensesAbstract_523A50968335A7669A46BAB9451F344C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SellingAndMarketingExpense" xlink:label="loc_us-gaap_SellingAndMarketingExpense_8A2B6B879B7F7C105A84BAB9451F650A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingExpensesAbstract_523A50968335A7669A46BAB9451F344C" xlink:to="loc_us-gaap_SellingAndMarketingExpense_8A2B6B879B7F7C105A84BAB9451F650A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ResearchAndDevelopmentExpenseSoftwareExcludingAcquiredInProcessCost" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpenseSoftwareExcludingAcquiredInProcessCost_BF89A273B2069185624EBAB9451FE2C8" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingExpensesAbstract_523A50968335A7669A46BAB9451F344C" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpenseSoftwareExcludingAcquiredInProcessCost_BF89A273B2069185624EBAB9451FE2C8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GeneralAndAdministrativeExpense" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_AC2A6A24F5C10BDB4DC9BAB9451F2390" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingExpensesAbstract_523A50968335A7669A46BAB9451F344C" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_AC2A6A24F5C10BDB4DC9BAB9451F2390" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AmortizationOfIntangibleAssets" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_E5CB095FFF9D9DCCFB13BAB9451F7DD7" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingExpensesAbstract_523A50968335A7669A46BAB9451F344C" xlink:to="loc_us-gaap_AmortizationOfIntangibleAssets_E5CB095FFF9D9DCCFB13BAB9451F7DD7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingExpenses" xlink:label="loc_us-gaap_OperatingExpenses_C36BB29AD2B03C387E08BAB945203458" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingExpensesAbstract_523A50968335A7669A46BAB9451F344C" xlink:to="loc_us-gaap_OperatingExpenses_C36BB29AD2B03C387E08BAB945203458" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_36BE2F2C29BF7575A5E2BAB945202D80" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementAbstract_BF3660C5EA74D7CB7781BAB9451F6ED4" xlink:to="loc_us-gaap_OperatingIncomeLoss_36BE2F2C29BF7575A5E2BAB945202D80" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherNonoperatingIncome" xlink:label="loc_us-gaap_OtherNonoperatingIncome_3A0EB806DEBAD9F3B863BAB94520F4FC" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementAbstract_BF3660C5EA74D7CB7781BAB9451F6ED4" xlink:to="loc_us-gaap_OtherNonoperatingIncome_3A0EB806DEBAD9F3B863BAB94520F4FC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaap_InterestExpense_C5933FFD4BB79878D0A1BAB945204C17" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementAbstract_BF3660C5EA74D7CB7781BAB9451F6ED4" xlink:to="loc_us-gaap_InterestExpense_C5933FFD4BB79878D0A1BAB945204C17" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_021D67413EDF5243542DBAB94520F50C" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementAbstract_BF3660C5EA74D7CB7781BAB9451F6ED4" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_021D67413EDF5243542DBAB94520F50C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_CCB0EEAF92DE6A2B8028BAB9452058AC" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementAbstract_BF3660C5EA74D7CB7781BAB9451F6ED4" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_CCB0EEAF92DE6A2B8028BAB9452058AC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_C472B5BA824E1E39AF20BAB945206AAA" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementAbstract_BF3660C5EA74D7CB7781BAB9451F6ED4" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_C472B5BA824E1E39AF20BAB945206AAA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_AAAA19FB336DA62B179BBAB94520059B" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementAbstract_BF3660C5EA74D7CB7781BAB9451F6ED4" xlink:to="loc_us-gaap_NetIncomeLoss_AAAA19FB336DA62B179BBAB94520059B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareBasic" xlink:label="loc_us-gaap_EarningsPerShareBasic_2F4597122E8ADD7AC10DBAB94520F541" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementAbstract_BF3660C5EA74D7CB7781BAB9451F6ED4" xlink:to="loc_us-gaap_EarningsPerShareBasic_2F4597122E8ADD7AC10DBAB94520F541" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareDiluted" xlink:label="loc_us-gaap_EarningsPerShareDiluted_ECF4E5B240874A3C632FBAB94520E840" xlink:type="locator" />
    <link:presentationArc order="13" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementAbstract_BF3660C5EA74D7CB7781BAB9451F6ED4" xlink:to="loc_us-gaap_EarningsPerShareDiluted_ECF4E5B240874A3C632FBAB94520E840" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_EC4808A1A1CF3614AFEDBAB94520A103" xlink:type="locator" />
    <link:presentationArc order="14" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementAbstract_BF3660C5EA74D7CB7781BAB9451F6ED4" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_EC4808A1A1CF3614AFEDBAB94520A103" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_F9647FBB05E0D9E98F7DBAB94520671A" xlink:type="locator" />
    <link:presentationArc order="15" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementAbstract_BF3660C5EA74D7CB7781BAB9451F6ED4" xlink:to="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_F9647FBB05E0D9E98F7DBAB94520671A" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/ConsolidatedStatementsOfStockholdersEquity" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementOfStockholdersEquityAbstract" xlink:label="loc_us-gaap_StatementOfStockholdersEquityAbstract_C78B6FBC3B99E7BD1439BC17C9B2FFC1" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable_ADCD26F7F67E03790BA1BC17C9B28D80" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfStockholdersEquityAbstract_C78B6FBC3B99E7BD1439BC17C9B2FFC1" xlink:to="loc_us-gaap_StatementTable_ADCD26F7F67E03790BA1BC17C9B28D80" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_D3DC4C2E2F0FF1049E23BC17C9B22E5D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementTable_ADCD26F7F67E03790BA1BC17C9B28D80" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_D3DC4C2E2F0FF1049E23BC17C9B22E5D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_6DA62270728F25E5DDFBBC17C9B2786F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_D3DC4C2E2F0FF1049E23BC17C9B22E5D" xlink:to="loc_us-gaap_EquityComponentDomain_6DA62270728F25E5DDFBBC17C9B2786F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember_15C131C21048EEE632C6BC17C9B2814E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityComponentDomain_6DA62270728F25E5DDFBBC17C9B2786F" xlink:to="loc_us-gaap_CommonStockMember_15C131C21048EEE632C6BC17C9B2814E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_3B50C6619AF6E57DE5A1BC17C9B2A80A" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityComponentDomain_6DA62270728F25E5DDFBBC17C9B2786F" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_3B50C6619AF6E57DE5A1BC17C9B2A80A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_FC2D0D1609E545AF2848BC17C9B22438" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityComponentDomain_6DA62270728F25E5DDFBBC17C9B2786F" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_FC2D0D1609E545AF2848BC17C9B22438" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaap_RetainedEarningsMember_3D0514F4DA83BF214D27BC17C9B2BB6D" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityComponentDomain_6DA62270728F25E5DDFBBC17C9B2786F" xlink:to="loc_us-gaap_RetainedEarningsMember_3D0514F4DA83BF214D27BC17C9B2BB6D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementTable_ADCD26F7F67E03790BA1BC17C9B28D80" xlink:to="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharesOutstanding" xlink:label="loc_us-gaap_SharesOutstanding_E5002410E1535075D4D8BC17C9B2EE75" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_SharesOutstanding_E5002410E1535075D4D8BC17C9B2EE75" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaap_StockholdersEquity_3C1EE1A46211440F83D8BC17C9B29D0D" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_StockholdersEquity_3C1EE1A46211440F83D8BC17C9B29D0D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption" xlink:label="loc_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_AC8DF5916115D9299B5EBC17C9B37E66" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_AC8DF5916115D9299B5EBC17C9B37E66" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_A4AAF1FBDAE3E1E87238BC17C9B3D031" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_NetIncomeLoss_A4AAF1FBDAE3E1E87238BC17C9B3D031" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_07CB31BFB9838D841E9EBC17C9B33FA7" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_07CB31BFB9838D841E9EBC17C9B33FA7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_B960A91459117911D1D1BC17C9B3694D" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_B960A91459117911D1D1BC17C9B3694D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_8372A185F8A4ABD8CEA7BC17C9B33CA0" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_8372A185F8A4ABD8CEA7BC17C9B33CA0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross_FECF71F4BED247782D32BC17C9B358C2" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross_FECF71F4BED247782D32BC17C9B358C2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardGross" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardGross_69FEFCE0E53B2CE147E5BC17C9B38AA4" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardGross_69FEFCE0E53B2CE147E5BC17C9B38AA4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalOther" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalOther_7A905B88DAEA90AFA1AABC17C9B361C7" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalOther_7A905B88DAEA90AFA1AABC17C9B361C7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation" xlink:label="loc_us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation_2084EAE4F24CB548DB29BC17C9B37180" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation_2084EAE4F24CB548DB29BC17C9B37180" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation" xlink:label="loc_us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation_E6AC8AFF085E64392E7CBC17C9B3B73F" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation_E6AC8AFF085E64392E7CBC17C9B3B73F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_490064E9ECFFCEAF019EBC17C9B3632D" xlink:type="locator" />
    <link:presentationArc order="13" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_490064E9ECFFCEAF019EBC17C9B3632D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_4E1FEFF94490956569D3BC17C9B3C38E" xlink:type="locator" />
    <link:presentationArc order="14" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_4E1FEFF94490956569D3BC17C9B3C38E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_21F647294493EE3EC7D6BC17C9B39A82" xlink:type="locator" />
    <link:presentationArc order="15" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_21F647294493EE3EC7D6BC17C9B39A82" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_05518F924D40F831674EBC17C9B3D063" xlink:type="locator" />
    <link:presentationArc order="16" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_05518F924D40F831674EBC17C9B3D063" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_912E57DC324E76B7D0D8BC17C9B35FEB" xlink:type="locator" />
    <link:presentationArc order="17" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_912E57DC324E76B7D0D8BC17C9B35FEB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxExpenseFromStockOptionsExercised" xlink:label="loc_us-gaap_DeferredTaxExpenseFromStockOptionsExercised_5ACF44C1FAED18848BAEBC17C9B3339E" xlink:type="locator" />
    <link:presentationArc order="18" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_DeferredTaxExpenseFromStockOptionsExercised_5ACF44C1FAED18848BAEBC17C9B3339E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharesOutstanding" xlink:label="loc_us-gaap_SharesOutstanding_E655A9E6CC226D230995BC17C9B3A675" xlink:type="locator" />
    <link:presentationArc order="19" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_SharesOutstanding_E655A9E6CC226D230995BC17C9B3A675" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaap_StockholdersEquity_9F23D06B0819596CA4A7BC17C9B4BA5D" xlink:type="locator" />
    <link:presentationArc order="20" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_C0E1E9C53FBC6B1F677CBC17C9B261AB" xlink:to="loc_us-gaap_StockholdersEquity_9F23D06B0819596CA4A7BC17C9B4BA5D" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/DocumentAndEntityInformation" xlink:type="extended">
    <link:loc xlink:href="csgp-20171231.xsd#csgp_DocumentAndEntityInformationAbstract" xlink:label="loc_csgp_DocumentAndEntityInformationAbstract_BA49BD0BA1E6602D761DDA91C429B926" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityRegistrantName" xlink:label="loc_dei_EntityRegistrantName_909B774EAD132D05AADEDA91C429E8AA" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_DocumentAndEntityInformationAbstract_BA49BD0BA1E6602D761DDA91C429B926" xlink:to="loc_dei_EntityRegistrantName_909B774EAD132D05AADEDA91C429E8AA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityCentralIndexKey" xlink:label="loc_dei_EntityCentralIndexKey_7F2321150E1020892C03DA91C4294A74" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_DocumentAndEntityInformationAbstract_BA49BD0BA1E6602D761DDA91C429B926" xlink:to="loc_dei_EntityCentralIndexKey_7F2321150E1020892C03DA91C4294A74" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_CurrentFiscalYearEndDate" xlink:label="loc_dei_CurrentFiscalYearEndDate_1AD016B9EF8D561D5607DA91C429C43F" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_DocumentAndEntityInformationAbstract_BA49BD0BA1E6602D761DDA91C429B926" xlink:to="loc_dei_CurrentFiscalYearEndDate_1AD016B9EF8D561D5607DA91C429C43F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityWellKnownSeasonedIssuer" xlink:label="loc_dei_EntityWellKnownSeasonedIssuer_A3B2CA38B1570E5CFE05DA91C4296831" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_DocumentAndEntityInformationAbstract_BA49BD0BA1E6602D761DDA91C429B926" xlink:to="loc_dei_EntityWellKnownSeasonedIssuer_A3B2CA38B1570E5CFE05DA91C4296831" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityVoluntaryFilers" xlink:label="loc_dei_EntityVoluntaryFilers_BB7BB8621616C1570AC0DA91C429858F" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_DocumentAndEntityInformationAbstract_BA49BD0BA1E6602D761DDA91C429B926" xlink:to="loc_dei_EntityVoluntaryFilers_BB7BB8621616C1570AC0DA91C429858F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityCurrentReportingStatus" xlink:label="loc_dei_EntityCurrentReportingStatus_04F9EC18C01CF440554BDA91C4295FFC" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_DocumentAndEntityInformationAbstract_BA49BD0BA1E6602D761DDA91C429B926" xlink:to="loc_dei_EntityCurrentReportingStatus_04F9EC18C01CF440554BDA91C4295FFC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityFilerCategory" xlink:label="loc_dei_EntityFilerCategory_811E94091D6A75F114DEDA91C42900CA" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_DocumentAndEntityInformationAbstract_BA49BD0BA1E6602D761DDA91C429B926" xlink:to="loc_dei_EntityFilerCategory_811E94091D6A75F114DEDA91C42900CA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityPublicFloat" xlink:label="loc_dei_EntityPublicFloat_FC5FA58BAB078E431AC0DA91C4296604" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_DocumentAndEntityInformationAbstract_BA49BD0BA1E6602D761DDA91C429B926" xlink:to="loc_dei_EntityPublicFloat_FC5FA58BAB078E431AC0DA91C4296604" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityCommonStockSharesOutstanding" xlink:label="loc_dei_EntityCommonStockSharesOutstanding_EFF57A73CB1FD34B2B5EDA91C4296B23" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_DocumentAndEntityInformationAbstract_BA49BD0BA1E6602D761DDA91C429B926" xlink:to="loc_dei_EntityCommonStockSharesOutstanding_EFF57A73CB1FD34B2B5EDA91C4296B23" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentFiscalYearFocus" xlink:label="loc_dei_DocumentFiscalYearFocus_1DCE96A7E8FBFEAF5888DA91C429F994" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_DocumentAndEntityInformationAbstract_BA49BD0BA1E6602D761DDA91C429B926" xlink:to="loc_dei_DocumentFiscalYearFocus_1DCE96A7E8FBFEAF5888DA91C429F994" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentFiscalPeriodFocus" xlink:label="loc_dei_DocumentFiscalPeriodFocus_793083F9079AE17F6D9EDA91C429A693" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_DocumentAndEntityInformationAbstract_BA49BD0BA1E6602D761DDA91C429B926" xlink:to="loc_dei_DocumentFiscalPeriodFocus_793083F9079AE17F6D9EDA91C429A693" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentType" xlink:label="loc_dei_DocumentType_6E7F5A9FD1810854B2BEDA91C429B694" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_DocumentAndEntityInformationAbstract_BA49BD0BA1E6602D761DDA91C429B926" xlink:to="loc_dei_DocumentType_6E7F5A9FD1810854B2BEDA91C429B694" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_AmendmentFlag" xlink:label="loc_dei_AmendmentFlag_872557BE82E9478B2FC4DA91C42A6427" xlink:type="locator" />
    <link:presentationArc order="13" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_DocumentAndEntityInformationAbstract_BA49BD0BA1E6602D761DDA91C429B926" xlink:to="loc_dei_AmendmentFlag_872557BE82E9478B2FC4DA91C42A6427" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentPeriodEndDate" xlink:label="loc_dei_DocumentPeriodEndDate_25F71F39A4DCFBCC5FFEDA91C42A6E10" xlink:type="locator" />
    <link:presentationArc order="14" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_DocumentAndEntityInformationAbstract_BA49BD0BA1E6602D761DDA91C429B926" xlink:to="loc_dei_DocumentPeriodEndDate_25F71F39A4DCFBCC5FFEDA91C42A6E10" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/EmployeeBenefitPlans" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CompensationRelatedCostsAbstract" xlink:label="loc_us-gaap_CompensationRelatedCostsAbstract_9A22414D6C00FA3A5B5BDA91C5290FD7" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" xlink:label="loc_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_0CD2169BFF599FCAA5AADA91C52953BF" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CompensationRelatedCostsAbstract_9A22414D6C00FA3A5B5BDA91C5290FD7" xlink:to="loc_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_0CD2169BFF599FCAA5AADA91C52953BF" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/EmployeeBenefitPlansDetailsForEmployee401KPlanEmployeePensionPlanRegisteredRetirementSavingsPlanAndEmployeeStockPurchasePlan" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CompensationAndRetirementDisclosureAbstract" xlink:label="loc_us-gaap_CompensationAndRetirementDisclosureAbstract_2D5AFD1FFA008F979CF7BAB341F2370F" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedContributionPlanTable" xlink:label="loc_us-gaap_DefinedContributionPlanTable_7CD3470FAD98FF6EAAF6BAB341F4145C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CompensationAndRetirementDisclosureAbstract_2D5AFD1FFA008F979CF7BAB341F2370F" xlink:to="loc_us-gaap_DefinedContributionPlanTable_7CD3470FAD98FF6EAAF6BAB341F4145C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RetirementPlanSponsorLocationAxis" xlink:label="loc_us-gaap_RetirementPlanSponsorLocationAxis_4A705DCF373C07A1FE82BAB341F5E431" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DefinedContributionPlanTable_7CD3470FAD98FF6EAAF6BAB341F4145C" xlink:to="loc_us-gaap_RetirementPlanSponsorLocationAxis_4A705DCF373C07A1FE82BAB341F5E431" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RetirementPlanSponsorLocationDomain" xlink:label="loc_us-gaap_RetirementPlanSponsorLocationDomain_8FE61934434CEAE6CB46BAB341F51C4B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RetirementPlanSponsorLocationAxis_4A705DCF373C07A1FE82BAB341F5E431" xlink:to="loc_us-gaap_RetirementPlanSponsorLocationDomain_8FE61934434CEAE6CB46BAB341F51C4B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ForeignPlanMember" xlink:label="loc_us-gaap_ForeignPlanMember_97520410903A470F17A6BAB341F57096" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RetirementPlanSponsorLocationDomain_8FE61934434CEAE6CB46BAB341F51C4B" xlink:to="loc_us-gaap_ForeignPlanMember_97520410903A470F17A6BAB341F57096" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaap_PlanNameAxis_6A967993D7679582EF55BAB341F57DEE" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DefinedContributionPlanTable_7CD3470FAD98FF6EAAF6BAB341F4145C" xlink:to="loc_us-gaap_PlanNameAxis_6A967993D7679582EF55BAB341F57DEE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaap_PlanNameDomain_2E487167C8D8507D8A7EBAB341F57568" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameAxis_6A967993D7679582EF55BAB341F57DEE" xlink:to="loc_us-gaap_PlanNameDomain_2E487167C8D8507D8A7EBAB341F57568" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_EmployeeStockPurchasePlanMember" xlink:label="loc_csgp_EmployeeStockPurchasePlanMember_EBF98A239AAA12036FE8BAB341F5BB1C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameDomain_2E487167C8D8507D8A7EBAB341F57568" xlink:to="loc_csgp_EmployeeStockPurchasePlanMember_EBF98A239AAA12036FE8BAB341F5BB1C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RetirementPlanTypeAxis" xlink:label="loc_us-gaap_RetirementPlanTypeAxis_4623AAA813414A8920C9BAB341F586A7" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DefinedContributionPlanTable_7CD3470FAD98FF6EAAF6BAB341F4145C" xlink:to="loc_us-gaap_RetirementPlanTypeAxis_4623AAA813414A8920C9BAB341F586A7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RetirementPlanTypeDomain" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_43A6873D02B380578534BAB341F6FAD9" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_4623AAA813414A8920C9BAB341F586A7" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_43A6873D02B380578534BAB341F6FAD9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherPensionPlansDefinedBenefitMember" xlink:label="loc_us-gaap_OtherPensionPlansDefinedBenefitMember_B53238BC92AED8398FC7BAB341F6271F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_43A6873D02B380578534BAB341F6FAD9" xlink:to="loc_us-gaap_OtherPensionPlansDefinedBenefitMember_B53238BC92AED8398FC7BAB341F6271F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SupplementalEmployeeRetirementPlanDefinedBenefitMember" xlink:label="loc_us-gaap_SupplementalEmployeeRetirementPlanDefinedBenefitMember_962E11A784D476CF1647BAB341F6BE55" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_43A6873D02B380578534BAB341F6FAD9" xlink:to="loc_us-gaap_SupplementalEmployeeRetirementPlanDefinedBenefitMember_962E11A784D476CF1647BAB341F6BE55" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedContributionPlanDisclosureLineItems" xlink:label="loc_us-gaap_DefinedContributionPlanDisclosureLineItems_FD2CC377FD07E3738F4BBAB341F61EB1" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DefinedContributionPlanTable_7CD3470FAD98FF6EAAF6BAB341F4145C" xlink:to="loc_us-gaap_DefinedContributionPlanDisclosureLineItems_FD2CC377FD07E3738F4BBAB341F61EB1" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_PercentageOfCompanyMatchOfEmployeeContribution" xlink:label="loc_csgp_PercentageOfCompanyMatchOfEmployeeContribution_84C65EA4AB5EC16858FDBAB341F6C5CC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DefinedContributionPlanDisclosureLineItems_FD2CC377FD07E3738F4BBAB341F61EB1" xlink:to="loc_csgp_PercentageOfCompanyMatchOfEmployeeContribution_84C65EA4AB5EC16858FDBAB341F6C5CC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch" xlink:label="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch_747EF658FDD13E16B15FBAB341F612FA" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DefinedContributionPlanDisclosureLineItems_FD2CC377FD07E3738F4BBAB341F61EB1" xlink:to="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch_747EF658FDD13E16B15FBAB341F612FA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedContributionPlanCostRecognized" xlink:label="loc_us-gaap_DefinedContributionPlanCostRecognized_D58AA5F11FD8B185CA41BAB341F62C14" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DefinedContributionPlanDisclosureLineItems_FD2CC377FD07E3738F4BBAB341F61EB1" xlink:to="loc_us-gaap_DefinedContributionPlanCostRecognized_D58AA5F11FD8B185CA41BAB341F62C14" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedContributionPlanAdministrativeExpenses" xlink:label="loc_us-gaap_DefinedContributionPlanAdministrativeExpenses_9F43ADF80D5EE3F8C896BAB341F6907A" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DefinedContributionPlanDisclosureLineItems_FD2CC377FD07E3738F4BBAB341F61EB1" xlink:to="loc_us-gaap_DefinedContributionPlanAdministrativeExpenses_9F43ADF80D5EE3F8C896BAB341F6907A" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_PercentageOfPurchasePriceOfCompanysCommonStockToMarketPrice" xlink:label="loc_csgp_PercentageOfPurchasePriceOfCompanysCommonStockToMarketPrice_517B457D1C903BB4D5B3BAB341F6F0DC" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DefinedContributionPlanDisclosureLineItems_FD2CC377FD07E3738F4BBAB341F61EB1" xlink:to="loc_csgp_PercentageOfPurchasePriceOfCompanysCommonStockToMarketPrice_517B457D1C903BB4D5B3BAB341F6F0DC" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_Increaseinsharesofcommonstockissuedpursuanttostockplan" xlink:label="loc_csgp_Increaseinsharesofcommonstockissuedpursuanttostockplan_FDF1AF7BA855A3AAA4A5BAB341F66BAC" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DefinedContributionPlanDisclosureLineItems_FD2CC377FD07E3738F4BBAB341F61EB1" xlink:to="loc_csgp_Increaseinsharesofcommonstockissuedpursuanttostockplan_FDF1AF7BA855A3AAA4A5BAB341F66BAC" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_SharesAvailableEmployeeStockPurchasePlan" xlink:label="loc_csgp_SharesAvailableEmployeeStockPurchasePlan_0BC212CA2A67CA0F85C8BAB341F6D926" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DefinedContributionPlanDisclosureLineItems_FD2CC377FD07E3738F4BBAB341F61EB1" xlink:to="loc_csgp_SharesAvailableEmployeeStockPurchasePlan_0BC212CA2A67CA0F85C8BAB341F6D926" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_AFA30ACAC013C529880FBAB341F68FF0" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DefinedContributionPlanDisclosureLineItems_FD2CC377FD07E3738F4BBAB341F61EB1" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_AFA30ACAC013C529880FBAB341F68FF0" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/EmployeeBenefitPlansDetailsForStockIncentivePlans" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CompensationRelatedCostsAbstract" xlink:label="loc_us-gaap_CompensationRelatedCostsAbstract_3E9C16914AAE67039791BAB38D0CB08F" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_40C4A26ED36D9E7FC031BAB38D0F9943" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CompensationRelatedCostsAbstract_3E9C16914AAE67039791BAB38D0CB08F" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_40C4A26ED36D9E7FC031BAB38D0F9943" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RetirementPlanSponsorLocationAxis" xlink:label="loc_us-gaap_RetirementPlanSponsorLocationAxis_8CC9CD41781311E87A56BAB38D0FB32F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_40C4A26ED36D9E7FC031BAB38D0F9943" xlink:to="loc_us-gaap_RetirementPlanSponsorLocationAxis_8CC9CD41781311E87A56BAB38D0FB32F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RetirementPlanSponsorLocationDomain" xlink:label="loc_us-gaap_RetirementPlanSponsorLocationDomain_D01982C689CCA4A9B35BBAB38D0F3A64" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RetirementPlanSponsorLocationAxis_8CC9CD41781311E87A56BAB38D0FB32F" xlink:to="loc_us-gaap_RetirementPlanSponsorLocationDomain_D01982C689CCA4A9B35BBAB38D0F3A64" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ForeignPlanMember" xlink:label="loc_us-gaap_ForeignPlanMember_C1B39F735ABE0499F100BAB38D0F0DA2" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RetirementPlanSponsorLocationDomain_D01982C689CCA4A9B35BBAB38D0F3A64" xlink:to="loc_us-gaap_ForeignPlanMember_C1B39F735ABE0499F100BAB38D0F0DA2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_8DCD7EDA4D8963357AE4BAB38D0F797D" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_40C4A26ED36D9E7FC031BAB38D0F9943" xlink:to="loc_us-gaap_RangeAxis_8DCD7EDA4D8963357AE4BAB38D0F797D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_DAFA476F0129280AE5E9BAB38D10B2D0" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RangeAxis_8DCD7EDA4D8963357AE4BAB38D0F797D" xlink:to="loc_us-gaap_RangeMember_DAFA476F0129280AE5E9BAB38D10B2D0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_CB068D9D718F7710AABBBAB38D10A3DB" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RangeMember_DAFA476F0129280AE5E9BAB38D10B2D0" xlink:to="loc_us-gaap_MinimumMember_CB068D9D718F7710AABBBAB38D10A3DB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_CA0582B35F3B2AB15DD8BAB38D106926" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RangeMember_DAFA476F0129280AE5E9BAB38D10B2D0" xlink:to="loc_us-gaap_MaximumMember_CA0582B35F3B2AB15DD8BAB38D106926" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaap_AwardTypeAxis_9487967DC7F9D5E9C464BAB38D10927F" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_40C4A26ED36D9E7FC031BAB38D0F9943" xlink:to="loc_us-gaap_AwardTypeAxis_9487967DC7F9D5E9C464BAB38D10927F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D709E589C34B3A23BAADBAB38D10A31A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AwardTypeAxis_9487967DC7F9D5E9C464BAB38D10927F" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D709E589C34B3A23BAADBAB38D10A31A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedStockUnitsRSUMember" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_76477C8E6B18DFD0B52BBAB38D1043E3" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D709E589C34B3A23BAADBAB38D10A31A" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_76477C8E6B18DFD0B52BBAB38D1043E3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="loc_us-gaap_EmployeeStockOptionMember_81A6234BCF7DAB8EDF4EBAB38D1020C5" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D709E589C34B3A23BAADBAB38D10A31A" xlink:to="loc_us-gaap_EmployeeStockOptionMember_81A6234BCF7DAB8EDF4EBAB38D1020C5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedStockMember" xlink:label="loc_us-gaap_RestrictedStockMember_8FF572210FDA8AD30B35BAB38D109DB8" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D709E589C34B3A23BAADBAB38D10A31A" xlink:to="loc_us-gaap_RestrictedStockMember_8FF572210FDA8AD30B35BAB38D109DB8" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_PerformanceBasedRSAsWithoutMarketConditionMember" xlink:label="loc_csgp_PerformanceBasedRSAsWithoutMarketConditionMember_44CBA44C30C1FBCFB5E5BAD80B47624C" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D709E589C34B3A23BAADBAB38D10A31A" xlink:to="loc_csgp_PerformanceBasedRSAsWithoutMarketConditionMember_44CBA44C30C1FBCFB5E5BAD80B47624C" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_PerformancebasedRSAswithMarketConditionMember" xlink:label="loc_csgp_PerformancebasedRSAswithMarketConditionMember_0DC9606A00593B171CC9BAB38D10D5A8" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D709E589C34B3A23BAADBAB38D10A31A" xlink:to="loc_csgp_PerformancebasedRSAswithMarketConditionMember_0DC9606A00593B171CC9BAB38D10D5A8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PerformanceSharesMember" xlink:label="loc_us-gaap_PerformanceSharesMember_624F84E2F3298ACFA3D9BAB38D105D2A" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D709E589C34B3A23BAADBAB38D10A31A" xlink:to="loc_us-gaap_PerformanceSharesMember_624F84E2F3298ACFA3D9BAB38D105D2A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaap_PlanNameAxis_259153ED71604632B9CBBAB38D106EDF" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_40C4A26ED36D9E7FC031BAB38D0F9943" xlink:to="loc_us-gaap_PlanNameAxis_259153ED71604632B9CBBAB38D106EDF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaap_PlanNameDomain_39065683BA8F620D2442BAB38D104D4B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameAxis_259153ED71604632B9CBBAB38D106EDF" xlink:to="loc_us-gaap_PlanNameDomain_39065683BA8F620D2442BAB38D104D4B" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_CoStarGroupInc.2016StockIncentivePlanMember" xlink:label="loc_csgp_CoStarGroupInc.2016StockIncentivePlanMember_D0C85F8FF2681DC7F70CBAB38D10F5CB" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameDomain_39065683BA8F620D2442BAB38D104D4B" xlink:to="loc_csgp_CoStarGroupInc.2016StockIncentivePlanMember_D0C85F8FF2681DC7F70CBAB38D10F5CB" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_CostarGroupInc2007StockIncentivePlanMember" xlink:label="loc_csgp_CostarGroupInc2007StockIncentivePlanMember_7947ED931281E283EAB5BAB38D10BA65" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameDomain_39065683BA8F620D2442BAB38D104D4B" xlink:to="loc_csgp_CostarGroupInc2007StockIncentivePlanMember_7947ED931281E283EAB5BAB38D10BA65" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis" xlink:label="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis_EEABECCD1461A417274CBAB38D114892" xlink:type="locator" />
    <link:presentationArc order="5" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_40C4A26ED36D9E7FC031BAB38D0F9943" xlink:to="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis_EEABECCD1461A417274CBAB38D114892" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain" xlink:label="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:type="locator" />
    <link:presentationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis_EEABECCD1461A417274CBAB38D114892" xlink:to="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsOutstanding1Member" xlink:label="loc_csgp_OptionsOutstanding1Member_489B882C3088B7916237BAB38D1175C5" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsOutstanding1Member_489B882C3088B7916237BAB38D1175C5" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsOutstanding2Member" xlink:label="loc_csgp_OptionsOutstanding2Member_AC4EB23D20348443136CBAB38D116750" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsOutstanding2Member_AC4EB23D20348443136CBAB38D116750" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsOutstanding3Member" xlink:label="loc_csgp_OptionsOutstanding3Member_7892C886D9A07340D6A4BAB38D115FA5" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsOutstanding3Member_7892C886D9A07340D6A4BAB38D115FA5" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsOutstanding4Member" xlink:label="loc_csgp_OptionsOutstanding4Member_2BFC32B7C5EAFB8A7D66BAB38D11FFD6" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsOutstanding4Member_2BFC32B7C5EAFB8A7D66BAB38D11FFD6" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsOutstanding5Member" xlink:label="loc_csgp_OptionsOutstanding5Member_3A82414AD66BEE2E3549BAB38D11D713" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsOutstanding5Member_3A82414AD66BEE2E3549BAB38D11D713" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsOutstanding6Member" xlink:label="loc_csgp_OptionsOutstanding6Member_A1E3338AB34F98DB06F8BAB38D116588" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsOutstanding6Member_A1E3338AB34F98DB06F8BAB38D116588" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsOutstanding7Member" xlink:label="loc_csgp_OptionsOutstanding7Member_CFF0AE596CC517A828C1BAB38D11075E" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsOutstanding7Member_CFF0AE596CC517A828C1BAB38D11075E" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsOutstanding8Member" xlink:label="loc_csgp_OptionsOutstanding8Member_D5EB5D24108EF96C1891BAB38D112A25" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsOutstanding8Member_D5EB5D24108EF96C1891BAB38D112A25" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsOutstanding9Member" xlink:label="loc_csgp_OptionsOutstanding9Member_C28A73C54888BB56530ABAB38D116878" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsOutstanding9Member_C28A73C54888BB56530ABAB38D116878" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsExercisable1Member" xlink:label="loc_csgp_OptionsExercisable1Member_EF2C68DBA3009BF75DF1BAB38D119D82" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsExercisable1Member_EF2C68DBA3009BF75DF1BAB38D119D82" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsExercisable2Member" xlink:label="loc_csgp_OptionsExercisable2Member_F60294BCC6C8BD4449C9BAB38D11A781" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsExercisable2Member_F60294BCC6C8BD4449C9BAB38D11A781" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsExercisable3Member" xlink:label="loc_csgp_OptionsExercisable3Member_EA7F28A32C75C7D06007BAB38D11FC55" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsExercisable3Member_EA7F28A32C75C7D06007BAB38D11FC55" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsExercisable4Member" xlink:label="loc_csgp_OptionsExercisable4Member_55E95335FC8CE33F9340BAB38D11546F" xlink:type="locator" />
    <link:presentationArc order="13" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsExercisable4Member_55E95335FC8CE33F9340BAB38D11546F" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsExercisable5Member" xlink:label="loc_csgp_OptionsExercisable5Member_4BBF4435375CEBD7D3D9BAB38D119A94" xlink:type="locator" />
    <link:presentationArc order="14" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsExercisable5Member_4BBF4435375CEBD7D3D9BAB38D119A94" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsExercisable6Member" xlink:label="loc_csgp_OptionsExercisable6Member_C09D9B69ACA4BBBC99CCBAB38D12E500" xlink:type="locator" />
    <link:presentationArc order="15" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsExercisable6Member_C09D9B69ACA4BBBC99CCBAB38D12E500" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsExercisable7Member" xlink:label="loc_csgp_OptionsExercisable7Member_D1FED9AADB95B0F9C467BAB38D12F0F3" xlink:type="locator" />
    <link:presentationArc order="16" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsExercisable7Member_D1FED9AADB95B0F9C467BAB38D12F0F3" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsExercisable8Member" xlink:label="loc_csgp_OptionsExercisable8Member_D5F22CB32CE788AC332DBAB38D124521" xlink:type="locator" />
    <link:presentationArc order="17" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsExercisable8Member_D5F22CB32CE788AC332DBAB38D124521" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsExercisable9Member" xlink:label="loc_csgp_OptionsExercisable9Member_B74D97C8091FDDB72F1BBAB38D129416" xlink:type="locator" />
    <link:presentationArc order="18" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeDomain_6A53B585C815EB6D921DBAB38D112165" xlink:to="loc_csgp_OptionsExercisable9Member_B74D97C8091FDDB72F1BBAB38D129416" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:type="locator" />
    <link:presentationArc order="6" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_40C4A26ED36D9E7FC031BAB38D0F9943" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_FE7A6FFE85B688CD42FFBAB38D12A601" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_FE7A6FFE85B688CD42FFBAB38D12A601" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_8D3191C4371C02C248C2BAB38D128C0E" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_8D3191C4371C02C248C2BAB38D128C0E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_BE2D88F9A5DC4B0EC887BAB38D121A12" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_BE2D88F9A5DC4B0EC887BAB38D121A12" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AllocatedShareBasedCompensationExpense" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_876CA003CB0A727D2676BAB38D120859" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_876CA003CB0A727D2676BAB38D120859" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_40B01A0EA3CF524DFE32BAB38D1273C2" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_40B01A0EA3CF524DFE32BAB38D1273C2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_D676773D729A93B98A04BAB38D1244B5" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_D676773D729A93B98A04BAB38D1244B5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_4A2276D6A97BEDBEC839BAB38D123636" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_4A2276D6A97BEDBEC839BAB38D123636" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_F6EF8E3F59B374948C10BAB38D128B4E" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_F6EF8E3F59B374948C10BAB38D128B4E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_CA2162E724ABDC72E545BAB38D12D0EE" xlink:type="locator" />
    <link:presentationArc order="9" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_CA2162E724ABDC72E545BAB38D12D0EE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_24D524E25078400E168CBAB38D126A08" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_CA2162E724ABDC72E545BAB38D12D0EE" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_24D524E25078400E168CBAB38D126A08" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_F3B4FBDC807E096F2DD5BAB38D12C483" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_CA2162E724ABDC72E545BAB38D12D0EE" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_F3B4FBDC807E096F2DD5BAB38D12C483" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_3DB4E6E84BEDE0CEC37CBAB38D12AA9D" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_CA2162E724ABDC72E545BAB38D12D0EE" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_3DB4E6E84BEDE0CEC37CBAB38D12AA9D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_F05DB58D3A43A38777C3BAB38D13007F" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_CA2162E724ABDC72E545BAB38D12D0EE" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_F05DB58D3A43A38777C3BAB38D13007F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_8ABDFF3F01ACD4A08E21BAB38D137369" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_CA2162E724ABDC72E545BAB38D12D0EE" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_8ABDFF3F01ACD4A08E21BAB38D137369" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_8F78D9FAD03669542C70BAB38D13F35C" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_CA2162E724ABDC72E545BAB38D12D0EE" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_8F78D9FAD03669542C70BAB38D13F35C" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_SharebasedCompensationSharesOutstandingUnderStockOptionPlansExercisePriceRange" xlink:label="loc_csgp_SharebasedCompensationSharesOutstandingUnderStockOptionPlansExercisePriceRange_B4FF2A7335D12E65D0B4BAB38D13BE37" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_CA2162E724ABDC72E545BAB38D12D0EE" xlink:to="loc_csgp_SharebasedCompensationSharesOutstandingUnderStockOptionPlansExercisePriceRange_B4FF2A7335D12E65D0B4BAB38D13BE37" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_SharebasedCompensationSharesGrantedUnderStockOptionPlansExercisePriceRange" xlink:label="loc_csgp_SharebasedCompensationSharesGrantedUnderStockOptionPlansExercisePriceRange_66D6A5ADE53835A973E0BAB38D13DB1E" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_CA2162E724ABDC72E545BAB38D12D0EE" xlink:to="loc_csgp_SharebasedCompensationSharesGrantedUnderStockOptionPlansExercisePriceRange_66D6A5ADE53835A973E0BAB38D13DB1E" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_SharebasedCompensationSharesExercisedUnderStockOptionPlansExercisePriceRange" xlink:label="loc_csgp_SharebasedCompensationSharesExercisedUnderStockOptionPlansExercisePriceRange_74CB31D0E94459FB9561BAB38D131665" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_CA2162E724ABDC72E545BAB38D12D0EE" xlink:to="loc_csgp_SharebasedCompensationSharesExercisedUnderStockOptionPlansExercisePriceRange_74CB31D0E94459FB9561BAB38D131665" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_SharebasedCompensationSharesCanceledorExpiredUnderStockOptionPlansExercisePriceRange" xlink:label="loc_csgp_SharebasedCompensationSharesCanceledorExpiredUnderStockOptionPlansExercisePriceRange_0A8DF4E3328C5155FB9ABAB38D13D387" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_CA2162E724ABDC72E545BAB38D12D0EE" xlink:to="loc_csgp_SharebasedCompensationSharesCanceledorExpiredUnderStockOptionPlansExercisePriceRange_0A8DF4E3328C5155FB9ABAB38D13D387" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_SharebasedCompensationSharesOutstandingUnderStockOptionPlansExercisePriceRange" xlink:label="loc_csgp_SharebasedCompensationSharesOutstandingUnderStockOptionPlansExercisePriceRange_EBFDC34B460615F6DF64BAB38D13D9E7" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_CA2162E724ABDC72E545BAB38D12D0EE" xlink:to="loc_csgp_SharebasedCompensationSharesOutstandingUnderStockOptionPlansExercisePriceRange_EBFDC34B460615F6DF64BAB38D13D9E7" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_Exercisableatendofperiod" xlink:label="loc_csgp_Exercisableatendofperiod_1524F8363F831FEAD142BAB38D1379A9" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_CA2162E724ABDC72E545BAB38D12D0EE" xlink:to="loc_csgp_Exercisableatendofperiod_1524F8363F831FEAD142BAB38D1379A9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_FC5C3054B04723450E55BAB38D138356" xlink:type="locator" />
    <link:presentationArc order="10" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_FC5C3054B04723450E55BAB38D138356" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_2B9ECF18D74FA57FDD63BAB38D13BA45" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_FC5C3054B04723450E55BAB38D138356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_2B9ECF18D74FA57FDD63BAB38D13BA45" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_5AACE9C84E99267C7440BAB38D13FA43" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_FC5C3054B04723450E55BAB38D138356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_5AACE9C84E99267C7440BAB38D13FA43" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_1BF2861DF25805D6A6B0BAB38D13E6B4" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_FC5C3054B04723450E55BAB38D138356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_1BF2861DF25805D6A6B0BAB38D13E6B4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_F40703F123BB7962569ABAB38D136760" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_FC5C3054B04723450E55BAB38D138356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_F40703F123BB7962569ABAB38D136760" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_F202873EB235D2825408BAB38D13FA22" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_FC5C3054B04723450E55BAB38D138356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_F202873EB235D2825408BAB38D13FA22" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_9E78149D63EBD3950C3BBAB38D13278E" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_FC5C3054B04723450E55BAB38D138356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_9E78149D63EBD3950C3BBAB38D13278E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_A85BBBAFC6092E6C8423BAB38D1357E4" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_FC5C3054B04723450E55BAB38D138356" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_A85BBBAFC6092E6C8423BAB38D1357E4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_F4BA9DDF2E022C2881B4BAB38D13AA65" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_FC5C3054B04723450E55BAB38D138356" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_F4BA9DDF2E022C2881B4BAB38D13AA65" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_4897B46616197B6F0082BAB38D13AFC5" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_FC5C3054B04723450E55BAB38D138356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_4897B46616197B6F0082BAB38D13AFC5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_231505CC2AEC65F2F8DFBAB38D14D8EE" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_FC5C3054B04723450E55BAB38D138356" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_231505CC2AEC65F2F8DFBAB38D14D8EE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_CB43B756E3D458BF0B97BAB38D149B36" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_CB43B756E3D458BF0B97BAB38D149B36" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_5362AF37A503A28EC648BAB38D14C475" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_5362AF37A503A28EC648BAB38D14C475" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_CC9F9800D2EF5D01DF21BAB38D14DD14" xlink:type="locator" />
    <link:presentationArc order="13" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_CC9F9800D2EF5D01DF21BAB38D14DD14" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_55308F7CF79EDED84466BAB38D147ED0" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_CC9F9800D2EF5D01DF21BAB38D14DD14" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_55308F7CF79EDED84466BAB38D147ED0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_417A43126AC548496902BAB38D148572" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_CC9F9800D2EF5D01DF21BAB38D14DD14" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_417A43126AC548496902BAB38D148572" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_4736C16E55BD64087F72BAB38D147659" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_CC9F9800D2EF5D01DF21BAB38D14DD14" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_4736C16E55BD64087F72BAB38D147659" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_144EA8C4F98FDCCE36E3BAB38D14A601" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_CC9F9800D2EF5D01DF21BAB38D14DD14" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_144EA8C4F98FDCCE36E3BAB38D14A601" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit" xlink:label="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit_53802F60DE810ECF6EDCBAB38D146645" xlink:type="locator" />
    <link:presentationArc order="14" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit_53802F60DE810ECF6EDCBAB38D146645" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit" xlink:label="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit_C004804AFF0EFBB4D605BAB38D149A02" xlink:type="locator" />
    <link:presentationArc order="15" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit_C004804AFF0EFBB4D605BAB38D149A02" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeEndOfPeriodAbstract" xlink:label="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeEndOfPeriodAbstract_57AD4FA6CF5CD80D71C7BAB38D145DDF" xlink:type="locator" />
    <link:presentationArc order="16" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeEndOfPeriodAbstract_57AD4FA6CF5CD80D71C7BAB38D145DDF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions" xlink:label="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions_43F7587E050C8C0CF296BAB38D14152D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeEndOfPeriodAbstract_57AD4FA6CF5CD80D71C7BAB38D145DDF" xlink:to="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions_43F7587E050C8C0CF296BAB38D14152D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageRemainingContractualTerm2" xlink:label="loc_us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageRemainingContractualTerm2_9C713243A74B559FA3A6BAB38D149F23" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeEndOfPeriodAbstract_57AD4FA6CF5CD80D71C7BAB38D145DDF" xlink:to="loc_us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageRemainingContractualTerm2_9C713243A74B559FA3A6BAB38D149F23" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1" xlink:label="loc_us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1_F184CA72456A1E9209FEBAB38D144DBD" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeEndOfPeriodAbstract_57AD4FA6CF5CD80D71C7BAB38D145DDF" xlink:to="loc_us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1_F184CA72456A1E9209FEBAB38D144DBD" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_OptionsExercisableAbstract" xlink:label="loc_csgp_OptionsExercisableAbstract_6B0D5B671FFBE98F5DEBBAB38D142906" xlink:type="locator" />
    <link:presentationArc order="17" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_csgp_OptionsExercisableAbstract_6B0D5B671FFBE98F5DEBBAB38D142906" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions" xlink:label="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions_FD63265ED8B7BCFA5DE5BAB38D144EAB" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_OptionsExercisableAbstract_6B0D5B671FFBE98F5DEBBAB38D142906" xlink:to="loc_us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions_FD63265ED8B7BCFA5DE5BAB38D144EAB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice1" xlink:label="loc_us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice1_8A9B9E0835423289BCC2BAB38D14D658" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_OptionsExercisableAbstract_6B0D5B671FFBE98F5DEBBAB38D142906" xlink:to="loc_us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice1_8A9B9E0835423289BCC2BAB38D14D658" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_D25C32A2021D567EC5E3BAB38D1484A3" xlink:type="locator" />
    <link:presentationArc order="18" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_D25C32A2021D567EC5E3BAB38D1484A3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_795407903CEC5AA80C75BAB38D15B7C2" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_D25C32A2021D567EC5E3BAB38D1484A3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_795407903CEC5AA80C75BAB38D15B7C2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_E54D09D1591729087F29BAB38D15BE30" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_D25C32A2021D567EC5E3BAB38D1484A3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_E54D09D1591729087F29BAB38D15BE30" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_E295D5BA062F7911C10CBAB38D15DF69" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_D25C32A2021D567EC5E3BAB38D1484A3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_E295D5BA062F7911C10CBAB38D15DF69" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_2EE43F9C6DBCDB91E4A9BAB38D15E35E" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_D25C32A2021D567EC5E3BAB38D1484A3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_2EE43F9C6DBCDB91E4A9BAB38D15E35E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_195D49C80AF5B8C92570BAB38D15F1E2" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_D25C32A2021D567EC5E3BAB38D1484A3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_195D49C80AF5B8C92570BAB38D15F1E2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_92439339ACFBBEFD6FA1BAB38D1534B2" xlink:type="locator" />
    <link:presentationArc order="19" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DF4AE6685C998B1D610DBAB38D123356" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_92439339ACFBBEFD6FA1BAB38D1534B2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_C252356D05ACF0BB159ABAB38D15725C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_92439339ACFBBEFD6FA1BAB38D1534B2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_C252356D05ACF0BB159ABAB38D15725C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_0AA789C64B2FE6BEB6ABBAB38D15A265" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_92439339ACFBBEFD6FA1BAB38D1534B2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_0AA789C64B2FE6BEB6ABBAB38D15A265" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_82E1BD12E233CE3FBDF8BAB38D15D3A0" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_92439339ACFBBEFD6FA1BAB38D1534B2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_82E1BD12E233CE3FBDF8BAB38D15D3A0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_1C6B765DC6C1E5B603FDBAB38D153819" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_92439339ACFBBEFD6FA1BAB38D1534B2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_1C6B765DC6C1E5B603FDBAB38D153819" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_D15ED78524D8ABBB1210BAB38D15F365" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_92439339ACFBBEFD6FA1BAB38D1534B2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_D15ED78524D8ABBB1210BAB38D15F365" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/EmployeeBenefitPlansPolicies" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CompensationRelatedCostsAbstract" xlink:label="loc_us-gaap_CompensationRelatedCostsAbstract_29B030C8AFEC9C0CBF28DA91C452D24A" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy" xlink:label="loc_us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_08480A67302CD78D8AB0DA91C4527EAF" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CompensationRelatedCostsAbstract_29B030C8AFEC9C0CBF28DA91C452D24A" xlink:to="loc_us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_08480A67302CD78D8AB0DA91C4527EAF" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/EmployeeBenefitPlansTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CompensationRelatedCostsAbstract" xlink:label="loc_us-gaap_CompensationRelatedCostsAbstract_77133711812F27A11FB9BAB9430C38C8" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_9527B48DF0A745E26C75BAB9430C89E5" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CompensationRelatedCostsAbstract_77133711812F27A11FB9BAB9430C38C8" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_9527B48DF0A745E26C75BAB9430C89E5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaap_AwardTypeAxis_DE8E687D30CC0F6FD0ABBAB9430CA93E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_9527B48DF0A745E26C75BAB9430C89E5" xlink:to="loc_us-gaap_AwardTypeAxis_DE8E687D30CC0F6FD0ABBAB9430CA93E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_3F3E08B9FD2701A37BFDBAB9430CF79F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AwardTypeAxis_DE8E687D30CC0F6FD0ABBAB9430CA93E" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_3F3E08B9FD2701A37BFDBAB9430CF79F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="loc_us-gaap_EmployeeStockOptionMember_3E0F8466C5F6D2DE311DBAB9430D2DFD" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_3F3E08B9FD2701A37BFDBAB9430CF79F" xlink:to="loc_us-gaap_EmployeeStockOptionMember_3E0F8466C5F6D2DE311DBAB9430D2DFD" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_PerformancebasedRSAswithMarketConditionMember" xlink:label="loc_csgp_PerformancebasedRSAswithMarketConditionMember_11FE073AA5BBBB899223BAB9430DBC17" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_3F3E08B9FD2701A37BFDBAB9430CF79F" xlink:to="loc_csgp_PerformancebasedRSAswithMarketConditionMember_11FE073AA5BBBB899223BAB9430DBC17" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedStockUnitsRSUMember" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_40C627ED23EF72C62861BAB9430D5556" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_3F3E08B9FD2701A37BFDBAB9430CF79F" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_40C627ED23EF72C62861BAB9430D5556" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_E499F7E6092E83C1D23CBAB9430DE17E" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_9527B48DF0A745E26C75BAB9430C89E5" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_E499F7E6092E83C1D23CBAB9430DE17E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_5743051D4BD08515E0C4BAB9430DC47F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_E499F7E6092E83C1D23CBAB9430DE17E" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_5743051D4BD08515E0C4BAB9430DC47F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock_3CE5C0C2A1D1A497E61DBAB9430D7F28" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_E499F7E6092E83C1D23CBAB9430DE17E" xlink:to="loc_us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock_3CE5C0C2A1D1A497E61DBAB9430D7F28" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeTextBlock" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeTextBlock_108EFAA2685B86A6477ABAB9430D3B60" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_E499F7E6092E83C1D23CBAB9430DE17E" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeTextBlock_108EFAA2685B86A6477ABAB9430D3B60" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock_62DC2217CDAD658DC368BAB9430D6BBE" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_E499F7E6092E83C1D23CBAB9430DE17E" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock_62DC2217CDAD658DC368BAB9430D6BBE" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/FairValue" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueDisclosuresAbstract" xlink:label="loc_us-gaap_FairValueDisclosuresAbstract_D42934837D33AC488939DA91C4607EF4" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueDisclosuresTextBlock" xlink:label="loc_us-gaap_FairValueDisclosuresTextBlock_D7FEB4BD79A8A48AA338DA91C4602FAE" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueDisclosuresAbstract_D42934837D33AC488939DA91C4607EF4" xlink:to="loc_us-gaap_FairValueDisclosuresTextBlock_D7FEB4BD79A8A48AA338DA91C4602FAE" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/FairValueDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueDisclosuresAbstract" xlink:label="loc_us-gaap_FairValueDisclosuresAbstract_B3985B50A13D9F5ACBD6BAB94445EDA4" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_99ABA557054B3888EB86BAB9444529E6" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueDisclosuresAbstract_B3985B50A13D9F5ACBD6BAB94445EDA4" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_99ABA557054B3888EB86BAB9444529E6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueByAssetClassAxis" xlink:label="loc_us-gaap_FairValueByAssetClassAxis_459CC9551DEA8FA089E7BAB94445A403" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_99ABA557054B3888EB86BAB9444529E6" xlink:to="loc_us-gaap_FairValueByAssetClassAxis_459CC9551DEA8FA089E7BAB94445A403" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_542019AF757235232123BAB944456E57" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_459CC9551DEA8FA089E7BAB94445A403" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_542019AF757235232123BAB944456E57" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AuctionRateSecuritiesMember" xlink:label="loc_us-gaap_AuctionRateSecuritiesMember_3B3488262F64CC130AD2BAB94446C268" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_542019AF757235232123BAB944456E57" xlink:to="loc_us-gaap_AuctionRateSecuritiesMember_3B3488262F64CC130AD2BAB94446C268" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueByMeasurementFrequencyAxis" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_89CF33FE60A008A26BE8BAB94446F436" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_99ABA557054B3888EB86BAB9444529E6" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_89CF33FE60A008A26BE8BAB94446F436" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueMeasurementFrequencyDomain" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_7559B37207AAA202EFEEBAB944466EDD" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_89CF33FE60A008A26BE8BAB94446F436" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_7559B37207AAA202EFEEBAB944466EDD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueMeasurementsRecurringMember" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_00DD27CE5ECE029CEDAFBAB94446E931" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_7559B37207AAA202EFEEBAB944466EDD" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_00DD27CE5ECE029CEDAFBAB94446E931" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_6BA8BBA4C24D0C388587BAB94446AD50" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_99ABA557054B3888EB86BAB9444529E6" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_6BA8BBA4C24D0C388587BAB94446AD50" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C7B008A0B28669FE10F8BAB9444651E9" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_6BA8BBA4C24D0C388587BAB94446AD50" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C7B008A0B28669FE10F8BAB9444651E9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueInputsLevel1Member" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_624D32BBA7ADEB96E45FBAB94446AE64" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C7B008A0B28669FE10F8BAB9444651E9" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_624D32BBA7ADEB96E45FBAB94446AE64" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueInputsLevel2Member" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_3757987865922856B309BAB94446A31E" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C7B008A0B28669FE10F8BAB9444651E9" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_3757987865922856B309BAB94446A31E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueInputsLevel3Member" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_C4CDEBEDC8E18261C69CBAB944469842" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C7B008A0B28669FE10F8BAB9444651E9" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_C4CDEBEDC8E18261C69CBAB944469842" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_1A25E28102168DACA5FBBAB944465D7C" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_99ABA557054B3888EB86BAB9444529E6" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_1A25E28102168DACA5FBBAB944465D7C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_0EF06C5FEFE6192A9F8CBAB944474DEB" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_1A25E28102168DACA5FBBAB944465D7C" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_0EF06C5FEFE6192A9F8CBAB944474DEB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MoneyMarketFundsMember" xlink:label="loc_us-gaap_MoneyMarketFundsMember_ED6AAC5BC300F065468DBAB94447F644" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_0EF06C5FEFE6192A9F8CBAB944474DEB" xlink:to="loc_us-gaap_MoneyMarketFundsMember_ED6AAC5BC300F065468DBAB94447F644" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommercialPaperMember" xlink:label="loc_us-gaap_CommercialPaperMember_8C6264EAA41970DB2AB7BAB94447591A" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_0EF06C5FEFE6192A9F8CBAB944474DEB" xlink:to="loc_us-gaap_CommercialPaperMember_8C6264EAA41970DB2AB7BAB94447591A" xlink:type="arc" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_0EF06C5FEFE6192A9F8CBAB944474DEB" xlink:to="loc_us-gaap_AuctionRateSecuritiesMember_3B3488262F64CC130AD2BAB94446C268" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_0F3FA944AB18DB00ACE0BAB944479E8B" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_99ABA557054B3888EB86BAB9444529E6" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_0F3FA944AB18DB00ACE0BAB944479E8B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AssetsFairValueDisclosureAbstract" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_D207D5B35B5D9CC3916FBAB944478515" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_0F3FA944AB18DB00ACE0BAB944479E8B" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_D207D5B35B5D9CC3916FBAB944478515" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AssetsFairValueDisclosure" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_AB0CB665CA3C94BD07CABAB944474C02" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_D207D5B35B5D9CC3916FBAB944478515" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_AB0CB665CA3C94BD07CABAB944474C02" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_65C34F4F06A8F1A6D42DBAB94447E569" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_D207D5B35B5D9CC3916FBAB944478515" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_65C34F4F06A8F1A6D42DBAB94447E569" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_297E385FC232716F0E2FBAB94447282A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_65C34F4F06A8F1A6D42DBAB94447E569" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_297E385FC232716F0E2FBAB94447282A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss_147754D321BAA1692FC8BAB9444796BE" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_65C34F4F06A8F1A6D42DBAB94447E569" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss_147754D321BAA1692FC8BAB9444796BE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements_008646F0622230401798BAB94447AC4F" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_65C34F4F06A8F1A6D42DBAB94447E569" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements_008646F0622230401798BAB94447AC4F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_C3DE57422EF0E467F60ABAB94447844D" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_65C34F4F06A8F1A6D42DBAB94447E569" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_C3DE57422EF0E467F60ABAB94447844D" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_AuctionRateSecuritiesVariableRateDebtInstrumentsInterestRateResetPeriod" xlink:label="loc_csgp_AuctionRateSecuritiesVariableRateDebtInstrumentsInterestRateResetPeriod_C220B97657FA4A5CA1A5BAB944471088" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_D207D5B35B5D9CC3916FBAB944478515" xlink:to="loc_csgp_AuctionRateSecuritiesVariableRateDebtInstrumentsInterestRateResetPeriod_C220B97657FA4A5CA1A5BAB944471088" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_MinimumContractualMaturitiesOnUnderlyingSecuritiesInvolvedInAuctionRateSecurities" xlink:label="loc_csgp_MinimumContractualMaturitiesOnUnderlyingSecuritiesInvolvedInAuctionRateSecurities_14734F848D63282CE633BAB94447592A" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_D207D5B35B5D9CC3916FBAB944478515" xlink:to="loc_csgp_MinimumContractualMaturitiesOnUnderlyingSecuritiesInvolvedInAuctionRateSecurities_14734F848D63282CE633BAB94447592A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableforsaleSecuritiesFailedAuctionValue" xlink:label="loc_us-gaap_AvailableforsaleSecuritiesFailedAuctionValue_3AF55B2C569C6CC6B78DBAB944484C1C" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_D207D5B35B5D9CC3916FBAB944478515" xlink:to="loc_us-gaap_AvailableforsaleSecuritiesFailedAuctionValue_3AF55B2C569C6CC6B78DBAB944484C1C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueInputsDiscountRate" xlink:label="loc_us-gaap_FairValueInputsDiscountRate_804D49441228D6D12BA4BAB9444892A7" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_D207D5B35B5D9CC3916FBAB944478515" xlink:to="loc_us-gaap_FairValueInputsDiscountRate_804D49441228D6D12BA4BAB9444892A7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_220E857AC0AD0A00AC40BAB94448C579" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_D207D5B35B5D9CC3916FBAB944478515" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_220E857AC0AD0A00AC40BAB94448C579" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/FairValueTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueDisclosuresAbstract" xlink:label="loc_us-gaap_FairValueDisclosuresAbstract_D4A192BA012A223E07B4DA91C511A20D" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisTextBlock" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisTextBlock_8E5F64B0B0AB63937CA5DA91C511256C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueDisclosuresAbstract_D4A192BA012A223E07B4DA91C511A20D" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisTextBlock_8E5F64B0B0AB63937CA5DA91C511256C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock_774B9467178681E16D60DA91C5110852" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueDisclosuresAbstract_D4A192BA012A223E07B4DA91C511A20D" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock_774B9467178681E16D60DA91C5110852" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/Goodwill" xlink:type="extended">
    <link:loc xlink:href="csgp-20171231.xsd#csgp_GoodwillAbstract" xlink:label="loc_csgp_GoodwillAbstract_0E71B6A14F78A72016AADA91C4BBC1E1" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GoodwillDisclosureTextBlock" xlink:label="loc_us-gaap_GoodwillDisclosureTextBlock_15D06D677380494CF274DA91C4BBF9EC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_GoodwillAbstract_0E71B6A14F78A72016AADA91C4BBC1E1" xlink:to="loc_us-gaap_GoodwillDisclosureTextBlock_15D06D677380494CF274DA91C4BBF9EC" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/GoodwillDetails" xlink:type="extended">
    <link:loc xlink:href="csgp-20171231.xsd#csgp_GoodwillAbstract" xlink:label="loc_csgp_GoodwillAbstract_33B0E2C636F22F141867BDDBDEE32F9B" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfGoodwillTable" xlink:label="loc_us-gaap_ScheduleOfGoodwillTable_81DB9F73615751166612BDDBDEE5F008" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_GoodwillAbstract_33B0E2C636F22F141867BDDBDEE32F9B" xlink:to="loc_us-gaap_ScheduleOfGoodwillTable_81DB9F73615751166612BDDBDEE5F008" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_20AB1ECB45B5E0355FF9BDDBDEE51619" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_81DB9F73615751166612BDDBDEE5F008" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_20AB1ECB45B5E0355FF9BDDBDEE51619" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_0238621A9FCDC797E09CBDDBDEE54E11" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_20AB1ECB45B5E0355FF9BDDBDEE51619" xlink:to="loc_us-gaap_SegmentDomain_0238621A9FCDC797E09CBDDBDEE54E11" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NorthAmericaMember" xlink:label="loc_us-gaap_NorthAmericaMember_EE640578F66B3D1CAA9CBDDBDEE5A863" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentDomain_0238621A9FCDC797E09CBDDBDEE54E11" xlink:to="loc_us-gaap_NorthAmericaMember_EE640578F66B3D1CAA9CBDDBDEE5A863" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EuropeMember" xlink:label="loc_us-gaap_EuropeMember_D29BF45B45AAF2BD994FBDDBDEE57986" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentDomain_0238621A9FCDC797E09CBDDBDEE54E11" xlink:to="loc_us-gaap_EuropeMember_D29BF45B45AAF2BD994FBDDBDEE57986" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_9F404046F80CAC062648BDDBDEE5B36F" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_81DB9F73615751166612BDDBDEE5F008" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_9F404046F80CAC062648BDDBDEE5B36F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_61A1A0EDC4023240C833BDDBDEE5F17D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_9F404046F80CAC062648BDDBDEE5B36F" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_61A1A0EDC4023240C833BDDBDEE5F17D" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_TheScreeningProsLLCMember" xlink:label="loc_csgp_TheScreeningProsLLCMember_1BCE9F6F4D25D2807D1FBDDBDEE6A911" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_61A1A0EDC4023240C833BDDBDEE5F17D" xlink:to="loc_csgp_TheScreeningProsLLCMember_1BCE9F6F4D25D2807D1FBDDBDEE6A911" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_ApartmentFinderMember" xlink:label="loc_csgp_ApartmentFinderMember_F488267729890AA9B7C4BDDBDEE6F907" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_61A1A0EDC4023240C833BDDBDEE5F17D" xlink:to="loc_csgp_ApartmentFinderMember_F488267729890AA9B7C4BDDBDEE6F907" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_IndependentDistributorBuyoutMember" xlink:label="loc_csgp_IndependentDistributorBuyoutMember_A91D0E287A9505B3C67FBDDBDEE6BA77" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_61A1A0EDC4023240C833BDDBDEE5F17D" xlink:to="loc_csgp_IndependentDistributorBuyoutMember_A91D0E287A9505B3C67FBDDBDEE6BA77" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_ThomasDailyMember" xlink:label="loc_csgp_ThomasDailyMember_9FD2A7E8EC5732D317C8BDDBDEE62B5A" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_61A1A0EDC4023240C833BDDBDEE5F17D" xlink:to="loc_csgp_ThomasDailyMember_9FD2A7E8EC5732D317C8BDDBDEE62B5A" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_WestsideRentalsMember" xlink:label="loc_csgp_WestsideRentalsMember_6F4C9F5D30616165D82CBDDBDEE68263" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_61A1A0EDC4023240C833BDDBDEE5F17D" xlink:to="loc_csgp_WestsideRentalsMember_6F4C9F5D30616165D82CBDDBDEE68263" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_LandWatchMember" xlink:label="loc_csgp_LandWatchMember_3A893FC2005F7CE46794BDDBDEE6B7E1" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_61A1A0EDC4023240C833BDDBDEE5F17D" xlink:to="loc_csgp_LandWatchMember_3A893FC2005F7CE46794BDDBDEE6B7E1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GoodwillLineItems" xlink:label="loc_us-gaap_GoodwillLineItems_054C4C0DC6FE0778F5F9BDDBDEE61263" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_81DB9F73615751166612BDDBDEE5F008" xlink:to="loc_us-gaap_GoodwillLineItems_054C4C0DC6FE0778F5F9BDDBDEE61263" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GoodwillRollForward" xlink:label="loc_us-gaap_GoodwillRollForward_DE4DEAA9DF9EA4F1B926BDDBDEE7AF04" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_GoodwillLineItems_054C4C0DC6FE0778F5F9BDDBDEE61263" xlink:to="loc_us-gaap_GoodwillRollForward_DE4DEAA9DF9EA4F1B926BDDBDEE7AF04" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_CBFB53B76ECF7B827E2DBDDBDEE777AB" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_GoodwillRollForward_DE4DEAA9DF9EA4F1B926BDDBDEE7AF04" xlink:to="loc_us-gaap_Goodwill_CBFB53B76ECF7B827E2DBDDBDEE777AB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GoodwillAcquiredDuringPeriod" xlink:label="loc_us-gaap_GoodwillAcquiredDuringPeriod_2EF84D0A86C3531E308FBDDBDEE7A7E7" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_GoodwillRollForward_DE4DEAA9DF9EA4F1B926BDDBDEE7AF04" xlink:to="loc_us-gaap_GoodwillAcquiredDuringPeriod_2EF84D0A86C3531E308FBDDBDEE7A7E7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GoodwillForeignCurrencyTranslationGainLoss" xlink:label="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_9E751D2D98EA4D2EF3E9BDDBDEE88AC9" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_GoodwillRollForward_DE4DEAA9DF9EA4F1B926BDDBDEE7AF04" xlink:to="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_9E751D2D98EA4D2EF3E9BDDBDEE88AC9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_3BD8432420E0CD18DD07BDDBDEE8B952" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_GoodwillRollForward_DE4DEAA9DF9EA4F1B926BDDBDEE7AF04" xlink:to="loc_us-gaap_Goodwill_3BD8432420E0CD18DD07BDDBDEE8B952" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount" xlink:label="loc_us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount_8AC4BD71DC709AFA7B1BBDDBDEE83797" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_GoodwillLineItems_054C4C0DC6FE0778F5F9BDDBDEE61263" xlink:to="loc_us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount_8AC4BD71DC709AFA7B1BBDDBDEE83797" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/GoodwillTables" xlink:type="extended">
    <link:loc xlink:href="csgp-20171231.xsd#csgp_GoodwillAbstract" xlink:label="loc_csgp_GoodwillAbstract_CC96A6DF481EE921D1B2DA91C422E4F9" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfGoodwillTextBlock" xlink:label="loc_us-gaap_ScheduleOfGoodwillTextBlock_9429CA41DCD463979CECDA91C4227C5D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_GoodwillAbstract_CC96A6DF481EE921D1B2DA91C422E4F9" xlink:to="loc_us-gaap_ScheduleOfGoodwillTextBlock_9429CA41DCD463979CECDA91C4227C5D" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/IncomeTaxes" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxDisclosureAbstract" xlink:label="loc_us-gaap_IncomeTaxDisclosureAbstract_9C26CBA50517ECADD108DA91C49948E2" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxDisclosureTextBlock" xlink:label="loc_us-gaap_IncomeTaxDisclosureTextBlock_D6D67CD072CA5A190EA3DA91C4990E97" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_9C26CBA50517ECADD108DA91C49948E2" xlink:to="loc_us-gaap_IncomeTaxDisclosureTextBlock_D6D67CD072CA5A190EA3DA91C4990E97" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/IncomeTaxesDetailsComponentsForProvisionForIncomeTaxes" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxDisclosureAbstract" xlink:label="loc_us-gaap_IncomeTaxDisclosureAbstract_7D603CD35A239D70B9A8E4A5ACB7D572" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CurrentIncomeTaxExpenseBenefitContinuingOperationsAbstract" xlink:label="loc_us-gaap_CurrentIncomeTaxExpenseBenefitContinuingOperationsAbstract_3528A4D296E97AA0E151E4A5ACB7A142" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_7D603CD35A239D70B9A8E4A5ACB7D572" xlink:to="loc_us-gaap_CurrentIncomeTaxExpenseBenefitContinuingOperationsAbstract_3528A4D296E97AA0E151E4A5ACB7A142" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CurrentFederalTaxExpenseBenefit" xlink:label="loc_us-gaap_CurrentFederalTaxExpenseBenefit_2C84291AA7FA663D847FE4A5ACB798A4" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CurrentIncomeTaxExpenseBenefitContinuingOperationsAbstract_3528A4D296E97AA0E151E4A5ACB7A142" xlink:to="loc_us-gaap_CurrentFederalTaxExpenseBenefit_2C84291AA7FA663D847FE4A5ACB798A4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CurrentStateAndLocalTaxExpenseBenefit" xlink:label="loc_us-gaap_CurrentStateAndLocalTaxExpenseBenefit_1D128DAAC3CE653961E7E4A5ACB70EA5" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CurrentIncomeTaxExpenseBenefitContinuingOperationsAbstract_3528A4D296E97AA0E151E4A5ACB7A142" xlink:to="loc_us-gaap_CurrentStateAndLocalTaxExpenseBenefit_1D128DAAC3CE653961E7E4A5ACB70EA5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CurrentForeignTaxExpenseBenefit" xlink:label="loc_us-gaap_CurrentForeignTaxExpenseBenefit_469690AFDB2DC83251BFE4A5ACB7EDDD" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CurrentIncomeTaxExpenseBenefitContinuingOperationsAbstract_3528A4D296E97AA0E151E4A5ACB7A142" xlink:to="loc_us-gaap_CurrentForeignTaxExpenseBenefit_469690AFDB2DC83251BFE4A5ACB7EDDD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CurrentIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_CurrentIncomeTaxExpenseBenefit_C5BDA5018660FBA71E50E4A5ACB7AF53" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CurrentIncomeTaxExpenseBenefitContinuingOperationsAbstract_3528A4D296E97AA0E151E4A5ACB7A142" xlink:to="loc_us-gaap_CurrentIncomeTaxExpenseBenefit_C5BDA5018660FBA71E50E4A5ACB7AF53" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract" xlink:label="loc_us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract_94A8AF794D83D452749AE4A5ACB70C2D" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_7D603CD35A239D70B9A8E4A5ACB7D572" xlink:to="loc_us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract_94A8AF794D83D452749AE4A5ACB70C2D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredFederalIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_FCA025780141F9679075E4A5ACB763D7" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract_94A8AF794D83D452749AE4A5ACB70C2D" xlink:to="loc_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_FCA025780141F9679075E4A5ACB763D7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_90136DDE22D6AB232E79E4A5ACB870E1" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract_94A8AF794D83D452749AE4A5ACB70C2D" xlink:to="loc_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_90136DDE22D6AB232E79E4A5ACB870E1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredForeignIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_DeferredForeignIncomeTaxExpenseBenefit_7636178AC132ED9EA7BEE4A5ACB84722" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract_94A8AF794D83D452749AE4A5ACB70C2D" xlink:to="loc_us-gaap_DeferredForeignIncomeTaxExpenseBenefit_7636178AC132ED9EA7BEE4A5ACB84722" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredOtherTaxExpenseBenefit" xlink:label="loc_us-gaap_DeferredOtherTaxExpenseBenefit_6483D37630228DB4D842E4A5ACB81485" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract_94A8AF794D83D452749AE4A5ACB70C2D" xlink:to="loc_us-gaap_DeferredOtherTaxExpenseBenefit_6483D37630228DB4D842E4A5ACB81485" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_B040A7542504319F2BC9E4A5ACB8EC6D" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_7D603CD35A239D70B9A8E4A5ACB7D572" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_B040A7542504319F2BC9E4A5ACB8EC6D" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/IncomeTaxesDetailsComponentsOfDeferredTaxAssetsAndLiabilities" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxDisclosureAbstract" xlink:label="loc_us-gaap_IncomeTaxDisclosureAbstract_E2457951B0C1A267B2FEBF4EF4708265" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxAssetsGrossAbstract" xlink:label="loc_us-gaap_DeferredTaxAssetsGrossAbstract_F4FF94C867B5E86F931FBF4EF4708619" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_E2457951B0C1A267B2FEBF4EF4708265" xlink:to="loc_us-gaap_DeferredTaxAssetsGrossAbstract_F4FF94C867B5E86F931FBF4EF4708619" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts_961030CA36431FC85B70BF4EF470D6A9" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredTaxAssetsGrossAbstract_F4FF94C867B5E86F931FBF4EF4708619" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts_961030CA36431FC85B70BF4EF470D6A9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation_B9AA5051D39ED0D3F2F5BF4EF470620F" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredTaxAssetsGrossAbstract_F4FF94C867B5E86F931FBF4EF4708619" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation_B9AA5051D39ED0D3F2F5BF4EF470620F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost_B3852A97C4043D559FBCBF4EF47077A9" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredTaxAssetsGrossAbstract_F4FF94C867B5E86F931FBF4EF4708619" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost_B3852A97C4043D559FBCBF4EF47077A9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxAssetsOperatingLossCarryforwards" xlink:label="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_F285FF0CFB1176DFD154BF4EF470A173" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredTaxAssetsGrossAbstract_F4FF94C867B5E86F931FBF4EF4708619" xlink:to="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_F285FF0CFB1176DFD154BF4EF470A173" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsReserves" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsReserves_24105BE684E0F8142FAABF4EF470AF80" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredTaxAssetsGrossAbstract_F4FF94C867B5E86F931FBF4EF4708619" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsReserves_24105BE684E0F8142FAABF4EF470AF80" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross" xlink:label="loc_us-gaap_DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross_A075666DB7D4A328314EBF4EF4704A70" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredTaxAssetsGrossAbstract_F4FF94C867B5E86F931FBF4EF4708619" xlink:to="loc_us-gaap_DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross_A075666DB7D4A328314EBF4EF4704A70" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsDeferredRent" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsDeferredRent_4E308E68F6478987EABABF4EF470B71C" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredTaxAssetsGrossAbstract_F4FF94C867B5E86F931FBF4EF4708619" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsDeferredRent_4E308E68F6478987EABABF4EF470B71C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxAssetsDeferredGainOnSaleLeasebackTransaction" xlink:label="loc_us-gaap_DeferredTaxAssetsDeferredGainOnSaleLeasebackTransaction_984FFF663D218B2B6B6EBF4EF470F8A7" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredTaxAssetsGrossAbstract_F4FF94C867B5E86F931FBF4EF4708619" xlink:to="loc_us-gaap_DeferredTaxAssetsDeferredGainOnSaleLeasebackTransaction_984FFF663D218B2B6B6EBF4EF470F8A7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxAssetsGross" xlink:label="loc_us-gaap_DeferredTaxAssetsGross_3A671C8BDAA8A18C10DEBF4EF470F3CD" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredTaxAssetsGrossAbstract_F4FF94C867B5E86F931FBF4EF4708619" xlink:to="loc_us-gaap_DeferredTaxAssetsGross_3A671C8BDAA8A18C10DEBF4EF470F3CD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxAssetsValuationAllowance" xlink:label="loc_us-gaap_DeferredTaxAssetsValuationAllowance_755FBD01B484E9B75D4DBF4EF4707B27" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredTaxAssetsGrossAbstract_F4FF94C867B5E86F931FBF4EF4708619" xlink:to="loc_us-gaap_DeferredTaxAssetsValuationAllowance_755FBD01B484E9B75D4DBF4EF4707B27" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxAssetsNet" xlink:label="loc_us-gaap_DeferredTaxAssetsNet_32211F48A6CE6183CDB9BF4EF47060BB" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredTaxAssetsGrossAbstract_F4FF94C867B5E86F931FBF4EF4708619" xlink:to="loc_us-gaap_DeferredTaxAssetsNet_32211F48A6CE6183CDB9BF4EF47060BB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxLiabilitiesAbstract" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesAbstract_86DCCA0EFCBA9204E056BF4EF47004DE" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_E2457951B0C1A267B2FEBF4EF4708265" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesAbstract_86DCCA0EFCBA9204E056BF4EF47004DE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxLiabilitiesPrepaidExpenses" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesPrepaidExpenses_E0D6E3EFE58473AE1D9DBF4EF471C754" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredTaxLiabilitiesAbstract_86DCCA0EFCBA9204E056BF4EF47004DE" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesPrepaidExpenses_E0D6E3EFE58473AE1D9DBF4EF471C754" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment_4454F8E5A896CBE93C51BF4EF47186CB" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredTaxLiabilitiesAbstract_86DCCA0EFCBA9204E056BF4EF47004DE" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment_4454F8E5A896CBE93C51BF4EF47186CB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssets" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssets_D2CC1EB3733FBAEE3936BF4EF471B9E2" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredTaxLiabilitiesAbstract_86DCCA0EFCBA9204E056BF4EF47004DE" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssets_D2CC1EB3733FBAEE3936BF4EF471B9E2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredIncomeTaxLiabilities" xlink:label="loc_us-gaap_DeferredIncomeTaxLiabilities_EF5E07C0D2AB2622E456BF4EF471A4CA" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredTaxLiabilitiesAbstract_86DCCA0EFCBA9204E056BF4EF47004DE" xlink:to="loc_us-gaap_DeferredIncomeTaxLiabilities_EF5E07C0D2AB2622E456BF4EF471A4CA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxLiabilities" xlink:label="loc_us-gaap_DeferredTaxLiabilities_98D0E8E751167757F2CEBF5F00E0B1AD" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_E2457951B0C1A267B2FEBF4EF4708265" xlink:to="loc_us-gaap_DeferredTaxLiabilities_98D0E8E751167757F2CEBF5F00E0B1AD" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/IncomeTaxesDetailsOther" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxDisclosureAbstract" xlink:label="loc_us-gaap_IncomeTaxDisclosureAbstract_668B86F9985A29CD27AEBF4EF462B106" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLossCarryforwardsTable" xlink:label="loc_us-gaap_OperatingLossCarryforwardsTable_B9039D727FA00D319AF9BF4EF4633D62" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_668B86F9985A29CD27AEBF4EF462B106" xlink:to="loc_us-gaap_OperatingLossCarryforwardsTable_B9039D727FA00D319AF9BF4EF4633D62" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TaxPeriodAxis" xlink:label="loc_us-gaap_TaxPeriodAxis_1774FED74D556EED421ABF4EF463005E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLossCarryforwardsTable_B9039D727FA00D319AF9BF4EF4633D62" xlink:to="loc_us-gaap_TaxPeriodAxis_1774FED74D556EED421ABF4EF463005E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TaxPeriodDomain" xlink:label="loc_us-gaap_TaxPeriodDomain_D0638CE2DDC8A9C6A015BF4EF463705B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_TaxPeriodAxis_1774FED74D556EED421ABF4EF463005E" xlink:to="loc_us-gaap_TaxPeriodDomain_D0638CE2DDC8A9C6A015BF4EF463705B" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_TaxYearsDecember312013ThroughDecember312017Member" xlink:label="loc_csgp_TaxYearsDecember312013ThroughDecember312017Member_815B2871B88E85C1D420BF4EF4633D39" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_TaxPeriodDomain_D0638CE2DDC8A9C6A015BF4EF463705B" xlink:to="loc_csgp_TaxYearsDecember312013ThroughDecember312017Member_815B2871B88E85C1D420BF4EF4633D39" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxAuthorityAxis" xlink:label="loc_us-gaap_IncomeTaxAuthorityAxis_D6C9F1A2CD63079D2CDABF4EF46323C3" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLossCarryforwardsTable_B9039D727FA00D319AF9BF4EF4633D62" xlink:to="loc_us-gaap_IncomeTaxAuthorityAxis_D6C9F1A2CD63079D2CDABF4EF46323C3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxAuthorityDomain" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_5985DDEAAC6083D9EE9BBF4EF463B19E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_D6C9F1A2CD63079D2CDABF4EF46323C3" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_5985DDEAAC6083D9EE9BBF4EF463B19E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ForeignCountryMember" xlink:label="loc_us-gaap_ForeignCountryMember_D75CE972E3B8FC8A2AC4BF4EF4630111" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_5985DDEAAC6083D9EE9BBF4EF463B19E" xlink:to="loc_us-gaap_ForeignCountryMember_D75CE972E3B8FC8A2AC4BF4EF4630111" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DomesticCountryMember" xlink:label="loc_us-gaap_DomesticCountryMember_31043D3EB9435439ADBEBF4EF463C364" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_5985DDEAAC6083D9EE9BBF4EF463B19E" xlink:to="loc_us-gaap_DomesticCountryMember_31043D3EB9435439ADBEBF4EF463C364" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StateAndLocalJurisdictionMember" xlink:label="loc_us-gaap_StateAndLocalJurisdictionMember_59654E5B312FBAE6AEF1BF4EF4636D1B" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_5985DDEAAC6083D9EE9BBF4EF463B19E" xlink:to="loc_us-gaap_StateAndLocalJurisdictionMember_59654E5B312FBAE6AEF1BF4EF4636D1B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLossCarryforwardsLineItems" xlink:label="loc_us-gaap_OperatingLossCarryforwardsLineItems_E5D300921BB4ADFF84D6BF4EF463A75C" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLossCarryforwardsTable_B9039D727FA00D319AF9BF4EF4633D62" xlink:to="loc_us-gaap_OperatingLossCarryforwardsLineItems_E5D300921BB4ADFF84D6BF4EF463A75C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount" xlink:label="loc_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_A4E885442F07D3C9FBDCBF4EF463F876" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_E5D300921BB4ADFF84D6BF4EF463A75C" xlink:to="loc_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_A4E885442F07D3C9FBDCBF4EF463F876" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLossCarryforwards" xlink:label="loc_us-gaap_OperatingLossCarryforwards_0317BF6E81720B27B9BFBF4EF463C008" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_E5D300921BB4ADFF84D6BF4EF463A75C" xlink:to="loc_us-gaap_OperatingLossCarryforwards_0317BF6E81720B27B9BFBF4EF463C008" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLossCarryforwardsExpirationDate" xlink:label="loc_us-gaap_OperatingLossCarryforwardsExpirationDate_FC563A43A3E61060B404BF4EF46385A2" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_E5D300921BB4ADFF84D6BF4EF463A75C" xlink:to="loc_us-gaap_OperatingLossCarryforwardsExpirationDate_FC563A43A3E61060B404BF4EF46385A2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TaxCreditCarryforwardAmount" xlink:label="loc_us-gaap_TaxCreditCarryforwardAmount_4B3BEB4B797892A64241BF4EF463BE2C" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_E5D300921BB4ADFF84D6BF4EF463A75C" xlink:to="loc_us-gaap_TaxCreditCarryforwardAmount_4B3BEB4B797892A64241BF4EF463BE2C" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_RealizedTaxBenefitsRelatedToOperatingLossCarryforward" xlink:label="loc_csgp_RealizedTaxBenefitsRelatedToOperatingLossCarryforward_4F42B16B22993A0E66E4BF4EF463FE47" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_E5D300921BB4ADFF84D6BF4EF463A75C" xlink:to="loc_csgp_RealizedTaxBenefitsRelatedToOperatingLossCarryforward_4F42B16B22993A0E66E4BF4EF463FE47" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReconciliationTaxCreditsResearch" xlink:label="loc_us-gaap_IncomeTaxReconciliationTaxCreditsResearch_B381BD5CF8423A34EAE6BF4EF4641D0A" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_E5D300921BB4ADFF84D6BF4EF463A75C" xlink:to="loc_us-gaap_IncomeTaxReconciliationTaxCreditsResearch_B381BD5CF8423A34EAE6BF4EF4641D0A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_41AAA1E189370D294862BF4EF464C4D3" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_668B86F9985A29CD27AEBF4EF462B106" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_41AAA1E189370D294862BF4EF464C4D3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_E3AA7E98966C76013E63BF4EF464DA6A" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_668B86F9985A29CD27AEBF4EF462B106" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_E3AA7E98966C76013E63BF4EF464DA6A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxesPaid" xlink:label="loc_us-gaap_IncomeTaxesPaid_6510868EADDED1034EF6BF4EF46405B0" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_668B86F9985A29CD27AEBF4EF462B106" xlink:to="loc_us-gaap_IncomeTaxesPaid_6510868EADDED1034EF6BF4EF46405B0" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/IncomeTaxesDetailsReconciliationOfProvisionForIncomeTaxes" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxDisclosureAbstract" xlink:label="loc_us-gaap_IncomeTaxDisclosureAbstract_8CDA414F9F704C3CE958BDDBDE534A0C" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_F5FC45223E393F2B93E7BDDBDE5358DA" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_8CDA414F9F704C3CE958BDDBDE534A0C" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_F5FC45223E393F2B93E7BDDBDE5358DA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate" xlink:label="loc_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_F5FAA1C3533395DA485CBDDBDE530DB8" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_F5FC45223E393F2B93E7BDDBDE5358DA" xlink:to="loc_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_F5FAA1C3533395DA485CBDDBDE530DB8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes" xlink:label="loc_us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes_BEA660CDA8EF0A4A1E4EBDDBDE530969" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_F5FC45223E393F2B93E7BDDBDE5358DA" xlink:to="loc_us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes_BEA660CDA8EF0A4A1E4EBDDBDE530969" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential" xlink:label="loc_us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential_C734A30BCF5B92AC2580BDDBDE55768F" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_F5FC45223E393F2B93E7BDDBDE5358DA" xlink:to="loc_us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential_C734A30BCF5B92AC2580BDDBDE55768F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance" xlink:label="loc_us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance_8D95EADB36A427179340BDDBDE556DAC" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_F5FC45223E393F2B93E7BDDBDE5358DA" xlink:to="loc_us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance_8D95EADB36A427179340BDDBDE556DAC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReconciliationNondeductibleExpense" xlink:label="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpense_9CD4C57E2D075D646AADBDDBDE556DF4" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_F5FC45223E393F2B93E7BDDBDE5358DA" xlink:to="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpense_9CD4C57E2D075D646AADBDDBDE556DF4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReconciliationNondeductibleExpenseOther" xlink:label="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpenseOther_83F374CB367C56DA5D31BDDBDE5562C4" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_F5FC45223E393F2B93E7BDDBDE5358DA" xlink:to="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpenseOther_83F374CB367C56DA5D31BDDBDE5562C4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReconciliationNondeductibleExpenseMealsAndEntertainment" xlink:label="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpenseMealsAndEntertainment_4CBE549B19E018640FDEBDDBDE55F97B" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_F5FC45223E393F2B93E7BDDBDE5358DA" xlink:to="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpenseMealsAndEntertainment_4CBE549B19E018640FDEBDDBDE55F97B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReconciliationChangeInEnactedTaxRate" xlink:label="loc_us-gaap_IncomeTaxReconciliationChangeInEnactedTaxRate_7AB9D75F0FD271569DEFBDDBDE55B785" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_F5FC45223E393F2B93E7BDDBDE5358DA" xlink:to="loc_us-gaap_IncomeTaxReconciliationChangeInEnactedTaxRate_7AB9D75F0FD271569DEFBDDBDE55B785" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReconciliationTaxCreditsResearch" xlink:label="loc_us-gaap_IncomeTaxReconciliationTaxCreditsResearch_7C08C1274FCDAED6457FBDDBDE556B40" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_F5FC45223E393F2B93E7BDDBDE5358DA" xlink:to="loc_us-gaap_IncomeTaxReconciliationTaxCreditsResearch_7C08C1274FCDAED6457FBDDBDE556B40" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_EffectiveIncomeTaxRateReconciliationExcessTaxBenefitAmount" xlink:label="loc_csgp_EffectiveIncomeTaxRateReconciliationExcessTaxBenefitAmount_1276CC66555B360C01E6BDE144D1434B" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_F5FC45223E393F2B93E7BDDBDE5358DA" xlink:to="loc_csgp_EffectiveIncomeTaxRateReconciliationExcessTaxBenefitAmount_1276CC66555B360C01E6BDE144D1434B" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_EffectiveIncomeTaxRateReconciliationChangeInTaxReservesAmount" xlink:label="loc_csgp_EffectiveIncomeTaxRateReconciliationChangeInTaxReservesAmount_CCE1605FB39F8605E9EABDE32E19B643" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_F5FC45223E393F2B93E7BDDBDE5358DA" xlink:to="loc_csgp_EffectiveIncomeTaxRateReconciliationChangeInTaxReservesAmount_CCE1605FB39F8605E9EABDE32E19B643" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReconciliationOtherAdjustments" xlink:label="loc_us-gaap_IncomeTaxReconciliationOtherAdjustments_9C12E6F8DAE410D144F2BDDBDE5549AA" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_F5FC45223E393F2B93E7BDDBDE5358DA" xlink:to="loc_us-gaap_IncomeTaxReconciliationOtherAdjustments_9C12E6F8DAE410D144F2BDDBDE5549AA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_A44978F941C72297684EBDDBDE558097" xlink:type="locator" />
    <link:presentationArc order="13" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_F5FC45223E393F2B93E7BDDBDE5358DA" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_A44978F941C72297684EBDDBDE558097" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/IncomeTaxesDetailsUnrecognizedTaxBenefits" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxDisclosureAbstract" xlink:label="loc_us-gaap_IncomeTaxDisclosureAbstract_2573EA9708065EF3F1F5BDDBDE3ED791" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ReconciliationOfUnrecognizedTaxBenefitsExcludingAmountsPertainingToExaminedTaxReturnsRollForward" xlink:label="loc_us-gaap_ReconciliationOfUnrecognizedTaxBenefitsExcludingAmountsPertainingToExaminedTaxReturnsRollForward_8C5E7BF57FFB059097E0BDDBDE3F0A7B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_2573EA9708065EF3F1F5BDDBDE3ED791" xlink:to="loc_us-gaap_ReconciliationOfUnrecognizedTaxBenefitsExcludingAmountsPertainingToExaminedTaxReturnsRollForward_8C5E7BF57FFB059097E0BDDBDE3F0A7B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UnrecognizedTaxBenefits" xlink:label="loc_us-gaap_UnrecognizedTaxBenefits_F4AA2A224350ED8322E5BDDBDE3FA9DC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationOfUnrecognizedTaxBenefitsExcludingAmountsPertainingToExaminedTaxReturnsRollForward_8C5E7BF57FFB059097E0BDDBDE3F0A7B" xlink:to="loc_us-gaap_UnrecognizedTaxBenefits_F4AA2A224350ED8322E5BDDBDE3FA9DC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions_66F85C7B5BCA0F78C85ABDDBDE3F29F2" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationOfUnrecognizedTaxBenefitsExcludingAmountsPertainingToExaminedTaxReturnsRollForward_8C5E7BF57FFB059097E0BDDBDE3F0A7B" xlink:to="loc_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions_66F85C7B5BCA0F78C85ABDDBDE3F29F2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions_129DE143FC80BFF964C9BDDBDE3F0380" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationOfUnrecognizedTaxBenefitsExcludingAmountsPertainingToExaminedTaxReturnsRollForward_8C5E7BF57FFB059097E0BDDBDE3F0A7B" xlink:to="loc_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions_129DE143FC80BFF964C9BDDBDE3F0380" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions_96A506002943BBB3DDAEBDDBDE3FC911" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationOfUnrecognizedTaxBenefitsExcludingAmountsPertainingToExaminedTaxReturnsRollForward_8C5E7BF57FFB059097E0BDDBDE3F0A7B" xlink:to="loc_us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions_96A506002943BBB3DDAEBDDBDE3FC911" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations_AE242FFA0C4BE3F31C65BDDBDE3F0BD0" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationOfUnrecognizedTaxBenefitsExcludingAmountsPertainingToExaminedTaxReturnsRollForward_8C5E7BF57FFB059097E0BDDBDE3F0A7B" xlink:to="loc_us-gaap_UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations_AE242FFA0C4BE3F31C65BDDBDE3F0BD0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UnrecognizedTaxBenefits" xlink:label="loc_us-gaap_UnrecognizedTaxBenefits_DB68191AF2994DEE2888BDDBDE3F1708" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationOfUnrecognizedTaxBenefitsExcludingAmountsPertainingToExaminedTaxReturnsRollForward_8C5E7BF57FFB059097E0BDDBDE3F0A7B" xlink:to="loc_us-gaap_UnrecognizedTaxBenefits_DB68191AF2994DEE2888BDDBDE3F1708" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate_FDB6E6BEBFD42AF7FE63BDDBDE3F8780" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_2573EA9708065EF3F1F5BDDBDE3ED791" xlink:to="loc_us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate_FDB6E6BEBFD42AF7FE63BDDBDE3F8780" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense_D4713AF7A25FFB883620BDDBDE4020D6" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_2573EA9708065EF3F1F5BDDBDE3ED791" xlink:to="loc_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense_D4713AF7A25FFB883620BDDBDE4020D6" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_UnrecognizedTaxBenefitsReversalOfInterestandPenalties" xlink:label="loc_csgp_UnrecognizedTaxBenefitsReversalOfInterestandPenalties_7AF2DA743CB539A6347EBDDBDE400879" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_2573EA9708065EF3F1F5BDDBDE3ED791" xlink:to="loc_csgp_UnrecognizedTaxBenefitsReversalOfInterestandPenalties_7AF2DA743CB539A6347EBDDBDE400879" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued_54F26ACA20E3B04F2867BDDBDE4098B3" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_2573EA9708065EF3F1F5BDDBDE3ED791" xlink:to="loc_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued_54F26ACA20E3B04F2867BDDBDE4098B3" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/IncomeTaxesTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxDisclosureAbstract" xlink:label="loc_us-gaap_IncomeTaxDisclosureAbstract_487E26D1AB4402807520DA91C4247617" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_9A854BEC5078FADA7EF3DA91C424D265" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_487E26D1AB4402807520DA91C4247617" xlink:to="loc_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_9A854BEC5078FADA7EF3DA91C424D265" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_E9EE3B6C793F1D415487DA91C424EC04" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_487E26D1AB4402807520DA91C4247617" xlink:to="loc_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_E9EE3B6C793F1D415487DA91C424EC04" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_6815980284AE58F115E2DA91C425FE0C" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_487E26D1AB4402807520DA91C4247617" xlink:to="loc_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_6815980284AE58F115E2DA91C425FE0C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock_967566102082B6040C9ADA91C4253318" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_487E26D1AB4402807520DA91C4247617" xlink:to="loc_us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock_967566102082B6040C9ADA91C4253318" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/IncomeTaxesTaxCutsAndJobsActOf2017Details" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxDisclosureAbstract" xlink:label="loc_us-gaap_IncomeTaxDisclosureAbstract_7AD1A7EBBB456C8352A0BDF5BD538302" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxContingencyTable" xlink:label="loc_us-gaap_IncomeTaxContingencyTable_6073DD3AD0DEAD498794BDF5C07DEA35" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_7AD1A7EBBB456C8352A0BDF5BD538302" xlink:to="loc_us-gaap_IncomeTaxContingencyTable_6073DD3AD0DEAD498794BDF5C07DEA35" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxAuthorityAxis" xlink:label="loc_us-gaap_IncomeTaxAuthorityAxis_2C6CB123F3EAA4AEF2D5BDF5C07DE758" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxContingencyTable_6073DD3AD0DEAD498794BDF5C07DEA35" xlink:to="loc_us-gaap_IncomeTaxAuthorityAxis_2C6CB123F3EAA4AEF2D5BDF5C07DE758" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxAuthorityDomain" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_C96EF20CA51DEA523D16BDF5C07DA9A8" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_2C6CB123F3EAA4AEF2D5BDF5C07DE758" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_C96EF20CA51DEA523D16BDF5C07DA9A8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxAuthorityNameAxis" xlink:label="loc_us-gaap_IncomeTaxAuthorityNameAxis_383D94AA5C400CD9066FBDF5C07DE01D" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxContingencyTable_6073DD3AD0DEAD498794BDF5C07DEA35" xlink:to="loc_us-gaap_IncomeTaxAuthorityNameAxis_383D94AA5C400CD9066FBDF5C07DE01D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxAuthorityNameDomain" xlink:label="loc_us-gaap_IncomeTaxAuthorityNameDomain_5A7B9BC6ECDD04290C4FBDF5C081DD9A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxAuthorityNameAxis_383D94AA5C400CD9066FBDF5C07DE01D" xlink:to="loc_us-gaap_IncomeTaxAuthorityNameDomain_5A7B9BC6ECDD04290C4FBDF5C081DD9A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TaxPeriodAxis" xlink:label="loc_us-gaap_TaxPeriodAxis_D48E444592EC75382E5BBDF5C0817218" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxContingencyTable_6073DD3AD0DEAD498794BDF5C07DEA35" xlink:to="loc_us-gaap_TaxPeriodAxis_D48E444592EC75382E5BBDF5C0817218" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TaxPeriodDomain" xlink:label="loc_us-gaap_TaxPeriodDomain_5B8FFEBBD69491FF89CBBDF5C0810115" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_TaxPeriodAxis_D48E444592EC75382E5BBDF5C0817218" xlink:to="loc_us-gaap_TaxPeriodDomain_5B8FFEBBD69491FF89CBBDF5C0810115" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxContingencyLineItems" xlink:label="loc_us-gaap_IncomeTaxContingencyLineItems_680E3729C1F210D501E7BDF5C0827BF8" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxContingencyTable_6073DD3AD0DEAD498794BDF5C07DEA35" xlink:to="loc_us-gaap_IncomeTaxContingencyLineItems_680E3729C1F210D501E7BDF5C0827BF8" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpense" xlink:label="loc_csgp_TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpense_F9BCBB410C2DAE2816A6BDFFB43A7DA9" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxContingencyLineItems_680E3729C1F210D501E7BDF5C0827BF8" xlink:to="loc_csgp_TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpense_F9BCBB410C2DAE2816A6BDFFB43A7DA9" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpense" xlink:label="loc_csgp_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpense_6D35B342AD38D7DF66E3BDF655B6D96F" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxContingencyLineItems_680E3729C1F210D501E7BDF5C0827BF8" xlink:to="loc_csgp_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpense_6D35B342AD38D7DF66E3BDF655B6D96F" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateProvisionalIncomeTaxExpense" xlink:label="loc_csgp_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateProvisionalIncomeTaxExpense_6EDE1219E19D90CE0CD7BDFCA0A90510" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeTaxContingencyLineItems_680E3729C1F210D501E7BDF5C0827BF8" xlink:to="loc_csgp_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateProvisionalIncomeTaxExpense_6EDE1219E19D90CE0CD7BDFCA0A90510" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/IntangibleAssets" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract_CA2A65F14901EBD2BD13DA91C56427F0" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IntangibleAssetsDisclosureTextBlock" xlink:label="loc_us-gaap_IntangibleAssetsDisclosureTextBlock_FD4B9084C0333132AD67DA91C564FE43" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract_CA2A65F14901EBD2BD13DA91C56427F0" xlink:to="loc_us-gaap_IntangibleAssetsDisclosureTextBlock_FD4B9084C0333132AD67DA91C564FE43" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/IntangibleAssetsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract_20E2959A85973585A6CCE480354EF137" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetByMajorClassTable" xlink:label="loc_us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetByMajorClassTable_5F3EF73D8872C37572B0E480354EB70C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract_20E2959A85973585A6CCE480354EF137" xlink:to="loc_us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetByMajorClassTable_5F3EF73D8872C37572B0E480354EB70C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_F66F3FA792111FEA7509E480354F0E3B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetByMajorClassTable_5F3EF73D8872C37572B0E480354EB70C" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_F66F3FA792111FEA7509E480354F0E3B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_59EFEFC6B75FC7F6FA14E480354F2887" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_F66F3FA792111FEA7509E480354F0E3B" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_59EFEFC6B75FC7F6FA14E480354F2887" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_LoopnetMember" xlink:label="loc_csgp_LoopnetMember_A583C1F7B2866C09B9D8E480354F5A63" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_59EFEFC6B75FC7F6FA14E480354F2887" xlink:to="loc_csgp_LoopnetMember_A583C1F7B2866C09B9D8E480354F5A63" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_2ACD8C0ADC8E853DBCE4E480354F5712" xlink:type="locator" />
    <link:presentationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetByMajorClassTable_5F3EF73D8872C37572B0E480354EB70C" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_2ACD8C0ADC8E853DBCE4E480354F5712" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_B6F3FFAC9F042568C92BE480354FC42C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_2ACD8C0ADC8E853DBCE4E480354F5712" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_B6F3FFAC9F042568C92BE480354FC42C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SoftwareAndSoftwareDevelopmentCostsMember" xlink:label="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_474E9BE812D83B98E9E7E480354F1D2E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_B6F3FFAC9F042568C92BE480354FC42C" xlink:to="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_474E9BE812D83B98E9E7E480354F1D2E" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_BuildingPhotographyMember" xlink:label="loc_csgp_BuildingPhotographyMember_7564E1FC3D9D91D80C68E480354F9615" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_B6F3FFAC9F042568C92BE480354FC42C" xlink:to="loc_csgp_BuildingPhotographyMember_7564E1FC3D9D91D80C68E480354F9615" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DevelopedTechnologyRightsMember" xlink:label="loc_us-gaap_DevelopedTechnologyRightsMember_439D54CB87D2B4C7D5A1E480354F4675" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_B6F3FFAC9F042568C92BE480354FC42C" xlink:to="loc_us-gaap_DevelopedTechnologyRightsMember_439D54CB87D2B4C7D5A1E480354F4675" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CustomerContractsMember" xlink:label="loc_us-gaap_CustomerContractsMember_14653989F25AC6584C5BE480354F4E24" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_B6F3FFAC9F042568C92BE480354FC42C" xlink:to="loc_us-gaap_CustomerContractsMember_14653989F25AC6584C5BE480354F4E24" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TradeNamesMember" xlink:label="loc_us-gaap_TradeNamesMember_06929B754CEE29105A30E480354F858E" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_B6F3FFAC9F042568C92BE480354FC42C" xlink:to="loc_us-gaap_TradeNamesMember_06929B754CEE29105A30E480354F858E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems" xlink:label="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems_DA39F9DE0484DEDE4B4CE480354FB696" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetByMajorClassTable_5F3EF73D8872C37572B0E480354EB70C" xlink:to="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems_DA39F9DE0484DEDE4B4CE480354FB696" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsGross" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_77E9AB7654C20B724889E480354F065C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems_DA39F9DE0484DEDE4B4CE480354FB696" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_77E9AB7654C20B724889E480354F065C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_A81EA187A043787DCDA7E480354FAC88" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems_DA39F9DE0484DEDE4B4CE480354FB696" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_A81EA187A043787DCDA7E480354FAC88" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsNet" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_016CAFF960B68BDA2E29E480354F99B2" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems_DA39F9DE0484DEDE4B4CE480354FB696" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_016CAFF960B68BDA2E29E480354F99B2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife" xlink:label="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_F0B88CF425B361D5E799E4803550C6DC" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems_DA39F9DE0484DEDE4B4CE480354FB696" xlink:to="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_F0B88CF425B361D5E799E4803550C6DC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdjustmentForAmortization" xlink:label="loc_us-gaap_AdjustmentForAmortization_9FCF9C5E2833EB32A88DE4803550ABAC" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems_DA39F9DE0484DEDE4B4CE480354FB696" xlink:to="loc_us-gaap_AdjustmentForAmortization_9FCF9C5E2833EB32A88DE4803550ABAC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_E43B8E8359B882E135BCE480355062A5" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract_20E2959A85973585A6CCE480354EF137" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_E43B8E8359B882E135BCE480355062A5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_A38F21FBE9BFA6D8E634E480355047F2" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_E43B8E8359B882E135BCE480355062A5" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_A38F21FBE9BFA6D8E634E480355047F2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_72D5368F7277775725C4E48035504751" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_E43B8E8359B882E135BCE480355062A5" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_72D5368F7277775725C4E48035504751" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_F95B956532ED99901BC2E4803550FAAC" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_E43B8E8359B882E135BCE480355062A5" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_F95B956532ED99901BC2E4803550FAAC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_3493D45B6777F16D7300E4803550E3BC" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_E43B8E8359B882E135BCE480355062A5" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_3493D45B6777F16D7300E4803550E3BC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_8D346D5E5C7A2A6F13E0E4803550D350" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_E43B8E8359B882E135BCE480355062A5" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_8D346D5E5C7A2A6F13E0E4803550D350" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/IntangibleAssetsTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract_1DBC0B87AEAB6D646813DA91C550982E" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetsByMajorClassTextBlock" xlink:label="loc_us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetsByMajorClassTextBlock_559AF05CD3C6B400B710DA91C5509AD4" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract_1DBC0B87AEAB6D646813DA91C550982E" xlink:to="loc_us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetsByMajorClassTextBlock_559AF05CD3C6B400B710DA91C5509AD4" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/Investments" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract" xlink:label="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_B6E508FF53295669BCAEDA91C4EB5170" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock" xlink:label="loc_us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock_EDAD73CE0605B1B56FC1DA91C4EBB15D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_B6E508FF53295669BCAEDA91C4EB5170" xlink:to="loc_us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock_EDAD73CE0605B1B56FC1DA91C4EBB15D" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/InvestmentsAvailableForSaleSecuritiesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract" xlink:label="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_67CD54CBE2322648FD54E46EEE0CDB92" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesTable" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_DFBE2FCC90B6B9D8E6F6E46EEE0C4D0A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_67CD54CBE2322648FD54E46EEE0CDB92" xlink:to="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_DFBE2FCC90B6B9D8E6F6E46EEE0C4D0A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_D74444D7FBCA3C8217F2E46EEE0CBB5C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_DFBE2FCC90B6B9D8E6F6E46EEE0C4D0A" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_D74444D7FBCA3C8217F2E46EEE0CBB5C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_E3811589987DFEB844A4E46EEE0D911D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_D74444D7FBCA3C8217F2E46EEE0CBB5C" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_E3811589987DFEB844A4E46EEE0D911D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AuctionRateSecuritiesMember" xlink:label="loc_us-gaap_AuctionRateSecuritiesMember_4B347A25513CF792CCABE46EEE0DEF2E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_E3811589987DFEB844A4E46EEE0D911D" xlink:to="loc_us-gaap_AuctionRateSecuritiesMember_4B347A25513CF792CCABE46EEE0DEF2E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_E8B2A2481EC5C8689A7AE46EEE0DBB13" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_DFBE2FCC90B6B9D8E6F6E46EEE0C4D0A" xlink:to="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_E8B2A2481EC5C8689A7AE46EEE0DBB13" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesAbstract" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesAbstract_F8644A8A35356C69FC03E46EEE0DDD6B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_E8B2A2481EC5C8689A7AE46EEE0DBB13" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesAbstract_F8644A8A35356C69FC03E46EEE0DDD6B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesAmortizedCost" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesAmortizedCost_E59C181DD7E31AEC6CE6E46EEE0D1D1C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesAbstract_F8644A8A35356C69FC03E46EEE0DDD6B" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesAmortizedCost_E59C181DD7E31AEC6CE6E46EEE0D1D1C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_1BA1C59EB3D4632E90ABE46EEE0D03E2" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesAbstract_F8644A8A35356C69FC03E46EEE0DDD6B" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_1BA1C59EB3D4632E90ABE46EEE0D03E2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_632C47DD2BD1FB551EF5E46EEE0D1B78" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesAbstract_F8644A8A35356C69FC03E46EEE0DDD6B" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_632C47DD2BD1FB551EF5E46EEE0D1B78" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecurities" xlink:label="loc_us-gaap_AvailableForSaleSecurities_F59638A362E9A178F082E46EEE0DE3DC" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesAbstract_F8644A8A35356C69FC03E46EEE0DDD6B" xlink:to="loc_us-gaap_AvailableForSaleSecurities_F59638A362E9A178F082E46EEE0DE3DC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract_1AD81AF0B2F531504E69E46EEE0D4B56" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_E8B2A2481EC5C8689A7AE46EEE0DBB13" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract_1AD81AF0B2F531504E69E46EEE0D4B56" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue_2EC9B4CD8902ACBFA443E46EEE0DED3F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract_1AD81AF0B2F531504E69E46EEE0D4B56" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue_2EC9B4CD8902ACBFA443E46EEE0DED3F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_755AA9574B2F5E3E3E51E46EEE0DB063" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract_1AD81AF0B2F531504E69E46EEE0D4B56" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_755AA9574B2F5E3E3E51E46EEE0DB063" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_ADEFF7B894F961E9CD4CE46EEE0D3E2B" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract_1AD81AF0B2F531504E69E46EEE0D4B56" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_ADEFF7B894F961E9CD4CE46EEE0D3E2B" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/InvestmentsPolicies" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract" xlink:label="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_CE058E2B67ED00F1AEFDDA91C4E9CE4F" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InvestmentPolicyTextBlock" xlink:label="loc_us-gaap_InvestmentPolicyTextBlock_0CA3AF92A9B488B873FCDA91C4E979F7" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_CE058E2B67ED00F1AEFDDA91C4E9CE4F" xlink:to="loc_us-gaap_InvestmentPolicyTextBlock_0CA3AF92A9B488B873FCDA91C4E979F7" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/InvestmentsScheduledMaturitiesAndRealizedGainsAndLossesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract" xlink:label="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_AF0063ED26C6D1B2179CAFECBC05C24B" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesGrossRealizedGains" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesGrossRealizedGains_2AFF8F1ED33854AD66FAAFECBC052E2B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_AF0063ED26C6D1B2179CAFECBC05C24B" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesGrossRealizedGains_2AFF8F1ED33854AD66FAAFECBC052E2B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesGrossRealizedGainsLossesSaleProceeds" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesGrossRealizedGainsLossesSaleProceeds_26DDFBF3507AFA915AA4AFECBC055446" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_AF0063ED26C6D1B2179CAFECBC05C24B" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesGrossRealizedGainsLossesSaleProceeds_26DDFBF3507AFA915AA4AFECBC055446" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses_EBCFEA7EBCD5BF41559DAFECBC05EC69" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_AF0063ED26C6D1B2179CAFECBC05C24B" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses_EBCFEA7EBCD5BF41559DAFECBC05EC69" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_2ED7DC42803D7A7BDA04AFECBC050E37" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_AF0063ED26C6D1B2179CAFECBC05C24B" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_2ED7DC42803D7A7BDA04AFECBC050E37" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_DCD4644E9B1AADCCF517AFECBC05E4C5" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_2ED7DC42803D7A7BDA04AFECBC050E37" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_DCD4644E9B1AADCCF517AFECBC05E4C5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_0F24354E17AFB89C2335AFECBC054AD0" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_2ED7DC42803D7A7BDA04AFECBC050E37" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_0F24354E17AFB89C2335AFECBC054AD0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_6E02E44091A48D0B67B2AFECBC05107F" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_2ED7DC42803D7A7BDA04AFECBC050E37" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_6E02E44091A48D0B67B2AFECBC05107F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue_ECB08C39C9B400A9E44AAFECBC05AFB1" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_2ED7DC42803D7A7BDA04AFECBC050E37" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue_ECB08C39C9B400A9E44AAFECBC05AFB1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecurities" xlink:label="loc_us-gaap_AvailableForSaleSecurities_1DBEE51D90446AAE4E27AFECBC05BEA3" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_2ED7DC42803D7A7BDA04AFECBC050E37" xlink:to="loc_us-gaap_AvailableForSaleSecurities_1DBEE51D90446AAE4E27AFECBC05BEA3" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/InvestmentsTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract" xlink:label="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_C981B18C25BF9487439FDA91C52598EE" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock" xlink:label="loc_us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock_2B10266F8DC114F3C1BCDA91C5254F86" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_C981B18C25BF9487439FDA91C52598EE" xlink:to="loc_us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock_2B10266F8DC114F3C1BCDA91C5254F86" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesReconciliationTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesReconciliationTableTextBlock_F6152ABA77E5BA85D298DA91C525B6B9" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_C981B18C25BF9487439FDA91C52598EE" xlink:to="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesReconciliationTableTextBlock_F6152ABA77E5BA85D298DA91C525B6B9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfUnrealizedLossOnInvestmentsTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfUnrealizedLossOnInvestmentsTableTextBlock_F9F5352362B170B09BE9DA91C5260C0E" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_C981B18C25BF9487439FDA91C52598EE" xlink:to="loc_us-gaap_ScheduleOfUnrealizedLossOnInvestmentsTableTextBlock_F9F5352362B170B09BE9DA91C5260C0E" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/LongTermDebt" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongtermDebtCurrentAndNoncurrentAbstract" xlink:label="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_743DF9EDCA110617A7FCDA91C4626475" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtTextBlock" xlink:label="loc_us-gaap_LongTermDebtTextBlock_BFC5E7732FFC5E68FD4ADA91C4627E5D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_743DF9EDCA110617A7FCDA91C4626475" xlink:to="loc_us-gaap_LongTermDebtTextBlock_BFC5E7732FFC5E68FD4ADA91C4627E5D" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/LongTermDebtDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongtermDebtCurrentAndNoncurrentAbstract" xlink:label="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_EC2D4BEB95994ABDAFCFBDDBDEB49AE4" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_64875FD99AF63BB3C470BDDBDEB44A7F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_EC2D4BEB95994ABDAFCFBDDBDEB49AE4" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_64875FD99AF63BB3C470BDDBDEB44A7F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VariableRateAxis" xlink:label="loc_us-gaap_VariableRateAxis_A0FBAD09E419D6B4A60EBDDBDEB40B1E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_64875FD99AF63BB3C470BDDBDEB44A7F" xlink:to="loc_us-gaap_VariableRateAxis_A0FBAD09E419D6B4A60EBDDBDEB40B1E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VariableRateDomain" xlink:label="loc_us-gaap_VariableRateDomain_3C389DBAA512D9383FC0BDDBDEB4B119" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_VariableRateAxis_A0FBAD09E419D6B4A60EBDDBDEB40B1E" xlink:to="loc_us-gaap_VariableRateDomain_3C389DBAA512D9383FC0BDDBDEB4B119" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_FederalFundsRateMember" xlink:label="loc_csgp_FederalFundsRateMember_E8DCAB76308C81D612FBBDDBDEB49997" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_VariableRateDomain_3C389DBAA512D9383FC0BDDBDEB4B119" xlink:to="loc_csgp_FederalFundsRateMember_E8DCAB76308C81D612FBBDDBDEB49997" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LondonInterbankOfferedRateLIBORMember" xlink:label="loc_us-gaap_LondonInterbankOfferedRateLIBORMember_83F8FDCDCB922B4A5F75BDDBDEB4E8BF" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_VariableRateDomain_3C389DBAA512D9383FC0BDDBDEB4B119" xlink:to="loc_us-gaap_LondonInterbankOfferedRateLIBORMember_83F8FDCDCB922B4A5F75BDDBDEB4E8BF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConsolidatedEntitiesAxis" xlink:label="loc_us-gaap_ConsolidatedEntitiesAxis_D55D187DCE01EACC1434BDDBDEB49E42" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_64875FD99AF63BB3C470BDDBDEB44A7F" xlink:to="loc_us-gaap_ConsolidatedEntitiesAxis_D55D187DCE01EACC1434BDDBDEB49E42" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConsolidatedEntitiesDomain" xlink:label="loc_us-gaap_ConsolidatedEntitiesDomain_E3E0AF82B11870A131E2BDDBDEB51EB3" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ConsolidatedEntitiesAxis_D55D187DCE01EACC1434BDDBDEB49E42" xlink:to="loc_us-gaap_ConsolidatedEntitiesDomain_E3E0AF82B11870A131E2BDDBDEB51EB3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ParentCompanyMember" xlink:label="loc_us-gaap_ParentCompanyMember_27196626C9812589A3D7BDDBDEB52E20" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ConsolidatedEntitiesDomain_E3E0AF82B11870A131E2BDDBDEB51EB3" xlink:to="loc_us-gaap_ParentCompanyMember_27196626C9812589A3D7BDDBDEB52E20" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_7D3E16913B1817FC0065BDDBDEB50D5C" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_64875FD99AF63BB3C470BDDBDEB44A7F" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_7D3E16913B1817FC0065BDDBDEB50D5C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_3973801652919C7AC9F5BDDBDEB5453E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_7D3E16913B1817FC0065BDDBDEB50D5C" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_3973801652919C7AC9F5BDDBDEB5453E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtMember" xlink:label="loc_us-gaap_LongTermDebtMember_1EC04E4BF82DEF17A2E1BDDBDEB5A6D7" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_3973801652919C7AC9F5BDDBDEB5453E" xlink:to="loc_us-gaap_LongTermDebtMember_1EC04E4BF82DEF17A2E1BDDBDEB5A6D7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevolvingCreditFacilityMember" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_8068813EDCECD5C186DEBDDBDEB5E97F" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_3973801652919C7AC9F5BDDBDEB5453E" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_8068813EDCECD5C186DEBDDBDEB5E97F" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_SwinglineLoanMember" xlink:label="loc_csgp_SwinglineLoanMember_992423C4DB0688B0807BBDDBDEB63E92" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_3973801652919C7AC9F5BDDBDEB5453E" xlink:to="loc_csgp_SwinglineLoanMember_992423C4DB0688B0807BBDDBDEB63E92" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LetterOfCreditMember" xlink:label="loc_us-gaap_LetterOfCreditMember_CA828B62BE758F9637CABDDBDEB6F940" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_3973801652919C7AC9F5BDDBDEB5453E" xlink:to="loc_us-gaap_LetterOfCreditMember_CA828B62BE758F9637CABDDBDEB6F940" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NotesPayableToBanksMember" xlink:label="loc_us-gaap_NotesPayableToBanksMember_BE5458F692E07DD0197BBDDBDEB6A68F" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_3973801652919C7AC9F5BDDBDEB5453E" xlink:to="loc_us-gaap_NotesPayableToBanksMember_BE5458F692E07DD0197BBDDBDEB6A68F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_64875FD99AF63BB3C470BDDBDEB44A7F" xlink:to="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount" xlink:label="loc_us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount_37E6AB5A067E6AF3F057BDDBDEB71463" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount_37E6AB5A067E6AF3F057BDDBDEB71463" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentTerm" xlink:label="loc_us-gaap_DebtInstrumentTerm_3B8AF7C6DAC48C4A6B99BDDBDEB77237" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_us-gaap_DebtInstrumentTerm_3B8AF7C6DAC48C4A6B99BDDBDEB77237" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCredit" xlink:label="loc_us-gaap_LineOfCredit_4D72F98B131C52F9086BBDDBDEB72FA6" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_us-gaap_LineOfCredit_4D72F98B131C52F9086BBDDBDEB72FA6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RepaymentsOfDebt" xlink:label="loc_us-gaap_RepaymentsOfDebt_065D9A48D650F6429CADBDDBDEB7AB64" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_us-gaap_RepaymentsOfDebt_065D9A48D650F6429CADBDDBDEB7AB64" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_7F9D279F2C0689AC7590BDDBDEB886ED" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_7F9D279F2C0689AC7590BDDBDEB886ED" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebt" xlink:label="loc_us-gaap_LongTermDebt_3110031A9D3EF6509D9DBDDBDEB8ADFD" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_us-gaap_LongTermDebt_3110031A9D3EF6509D9DBDDBDEB8ADFD" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_PercentageOfLoanAmortizationInYearOne" xlink:label="loc_csgp_PercentageOfLoanAmortizationInYearOne_DE05163CEBBED1076832BDDBDEB81CC2" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_csgp_PercentageOfLoanAmortizationInYearOne_DE05163CEBBED1076832BDDBDEB81CC2" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_PercentageOfLoanAmortizationInYearTwo" xlink:label="loc_csgp_PercentageOfLoanAmortizationInYearTwo_12E2288333E8C5FE7F90BDDBDEB8262B" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_csgp_PercentageOfLoanAmortizationInYearTwo_12E2288333E8C5FE7F90BDDBDEB8262B" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_PercentageOfLoanAmortizationInYearThree" xlink:label="loc_csgp_PercentageOfLoanAmortizationInYearThree_F2148A8BBE6BCB1BCF9ABDDBDEB82BB0" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_csgp_PercentageOfLoanAmortizationInYearThree_F2148A8BBE6BCB1BCF9ABDDBDEB82BB0" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_PercentageOfLoanAmortizationInYearFour" xlink:label="loc_csgp_PercentageOfLoanAmortizationInYearFour_500A655F6A0ADC519CFFBDDBDEB8A89C" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_csgp_PercentageOfLoanAmortizationInYearFour_500A655F6A0ADC519CFFBDDBDEB8A89C" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_PercentageOfLoanAmortizationInYearFive" xlink:label="loc_csgp_PercentageOfLoanAmortizationInYearFive_ACEDA9C10CAFEB95A48DBDDBDEB80D6E" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_csgp_PercentageOfLoanAmortizationInYearFive_ACEDA9C10CAFEB95A48DBDDBDEB80D6E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_654427C2E967F2A921C1BDDBDEB899C8" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_654427C2E967F2A921C1BDDBDEB899C8" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_LiborMaturityPeriod" xlink:label="loc_csgp_LiborMaturityPeriod_62FD94BCD9C575444228BDDBDEB924F2" xlink:type="locator" />
    <link:presentationArc order="13" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_csgp_LiborMaturityPeriod_62FD94BCD9C575444228BDDBDEB924F2" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_DebtInstrumentBasisSpreadOnVariableRateOneMonthInterestPeriod" xlink:label="loc_csgp_DebtInstrumentBasisSpreadOnVariableRateOneMonthInterestPeriod_88B0ED64DF2EFC756F36BDDBDEB94DA3" xlink:type="locator" />
    <link:presentationArc order="14" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_csgp_DebtInstrumentBasisSpreadOnVariableRateOneMonthInterestPeriod_88B0ED64DF2EFC756F36BDDBDEB94DA3" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_DebtInstrumentBasisSpreadOnVariableRatePerAnnum" xlink:label="loc_csgp_DebtInstrumentBasisSpreadOnVariableRatePerAnnum_C1D3713F25ACD77D4BF3BDDBDEB94F94" xlink:type="locator" />
    <link:presentationArc order="15" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_csgp_DebtInstrumentBasisSpreadOnVariableRatePerAnnum_C1D3713F25ACD77D4BF3BDDBDEB94F94" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_DefaultInterestRateSpreadPerAnnum" xlink:label="loc_csgp_DefaultInterestRateSpreadPerAnnum_AD1BAFB8250C2BBCDDEBBDDBDEB9D82B" xlink:type="locator" />
    <link:presentationArc order="16" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_csgp_DefaultInterestRateSpreadPerAnnum_AD1BAFB8250C2BBCDDEBBDDBDEB9D82B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityCollateral" xlink:label="loc_us-gaap_LineOfCreditFacilityCollateral_F8CD297F788B9D634862BDDBDEB9684E" xlink:type="locator" />
    <link:presentationArc order="17" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0B1FFFDA90D8B4352E29BDDBDEB7F513" xlink:to="loc_us-gaap_LineOfCreditFacilityCollateral_F8CD297F788B9D634862BDDBDEB9684E" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/LongTermDebtDetailsComponentsOfLongTermDebt" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtDisclosureAbstract" xlink:label="loc_us-gaap_DebtDisclosureAbstract_74B2B0FB1A3B2184AA05E489EDAF620C" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentCarryingAmount" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_ACED7795703CE08B1E1CE489EDB5B2C6" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtDisclosureAbstract_74B2B0FB1A3B2184AA05E489EDAF620C" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_ACED7795703CE08B1E1CE489EDB5B2C6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredFinanceCostsNet" xlink:label="loc_us-gaap_DeferredFinanceCostsNet_96C49A0484A84A20BC95E489EDB54014" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtDisclosureAbstract_74B2B0FB1A3B2184AA05E489EDAF620C" xlink:to="loc_us-gaap_DeferredFinanceCostsNet_96C49A0484A84A20BC95E489EDB54014" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebt" xlink:label="loc_us-gaap_LongTermDebt_A473DA6FFEFAA48BF937E489EDB53DA9" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtDisclosureAbstract_74B2B0FB1A3B2184AA05E489EDAF620C" xlink:to="loc_us-gaap_LongTermDebt_A473DA6FFEFAA48BF937E489EDB53DA9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherLongTermDebtCurrent" xlink:label="loc_us-gaap_OtherLongTermDebtCurrent_C48A713A088F24566F9DE489EDB51B9A" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtDisclosureAbstract_74B2B0FB1A3B2184AA05E489EDAF620C" xlink:to="loc_us-gaap_OtherLongTermDebtCurrent_C48A713A088F24566F9DE489EDB51B9A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredFinanceCostsCurrentNet" xlink:label="loc_us-gaap_DeferredFinanceCostsCurrentNet_D8D833D18AC5549DF648E489EDB57A4F" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtDisclosureAbstract_74B2B0FB1A3B2184AA05E489EDAF620C" xlink:to="loc_us-gaap_DeferredFinanceCostsCurrentNet_D8D833D18AC5549DF648E489EDB57A4F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_504CC8987B991431CA24E489EDB5BAC7" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtDisclosureAbstract_74B2B0FB1A3B2184AA05E489EDAF620C" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_504CC8987B991431CA24E489EDB5BAC7" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/LongTermDebtDetailsCovenantCalculations" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtDisclosureAbstract" xlink:label="loc_us-gaap_DebtDisclosureAbstract_71291021B50FB0B4DB7ABCCCC56FA61A" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_493BFDD17118A55D2211BCCCC56F4DB1" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtDisclosureAbstract_71291021B50FB0B4DB7ABCCCC56FA61A" xlink:to="loc_us-gaap_DebtInstrumentTable_493BFDD17118A55D2211BCCCC56F4DB1" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_VariableRateComponentAxis" xlink:label="loc_csgp_VariableRateComponentAxis_B50CA017D14040D60A34BCCCC56F5003" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_493BFDD17118A55D2211BCCCC56F4DB1" xlink:to="loc_csgp_VariableRateComponentAxis_B50CA017D14040D60A34BCCCC56F5003" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_VariableRateComponentDomain" xlink:label="loc_csgp_VariableRateComponentDomain_833B0F0490B581B33A2ABCCCC56F1BFB" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_VariableRateComponentAxis_B50CA017D14040D60A34BCCCC56F5003" xlink:to="loc_csgp_VariableRateComponentDomain_833B0F0490B581B33A2ABCCCC56F1BFB" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_InitialBasisSpreadMember" xlink:label="loc_csgp_InitialBasisSpreadMember_1FC84E36B59991BA359FBCCCC56F6B24" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_VariableRateComponentDomain_833B0F0490B581B33A2ABCCCC56F1BFB" xlink:to="loc_csgp_InitialBasisSpreadMember_1FC84E36B59991BA359FBCCCC56F6B24" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_InitialBasisSpreadOneMonthLIBORMember" xlink:label="loc_csgp_InitialBasisSpreadOneMonthLIBORMember_E1E74737A9356BC1F8C1BCCCC56FE7DC" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_csgp_VariableRateComponentDomain_833B0F0490B581B33A2ABCCCC56F1BFB" xlink:to="loc_csgp_InitialBasisSpreadOneMonthLIBORMember_E1E74737A9356BC1F8C1BCCCC56FE7DC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CreditFacilityAxis" xlink:label="loc_us-gaap_CreditFacilityAxis_D18DBCE1BDF4A7685014BCCCC56FE923" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_493BFDD17118A55D2211BCCCC56F4DB1" xlink:to="loc_us-gaap_CreditFacilityAxis_D18DBCE1BDF4A7685014BCCCC56FE923" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_B4FCE95DDB75289C85EEBCCCC56FDB34" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CreditFacilityAxis_D18DBCE1BDF4A7685014BCCCC56FE923" xlink:to="loc_us-gaap_CreditFacilityDomain_B4FCE95DDB75289C85EEBCCCC56FDB34" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevolvingCreditFacilityMember" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_181E20DFC806F97904CABCCCC56F060F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CreditFacilityDomain_B4FCE95DDB75289C85EEBCCCC56FDB34" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_181E20DFC806F97904CABCCCC56F060F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LetterOfCreditMember" xlink:label="loc_us-gaap_LetterOfCreditMember_417B940487DB28A4F64CBCCCC56F72B2" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CreditFacilityDomain_B4FCE95DDB75289C85EEBCCCC56FDB34" xlink:to="loc_us-gaap_LetterOfCreditMember_417B940487DB28A4F64CBCCCC56F72B2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_A68428176FA4BAA1975EBCCCC56F815B" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_493BFDD17118A55D2211BCCCC56F4DB1" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_A68428176FA4BAA1975EBCCCC56F815B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_1A3B6C2F73AB8BBD50C4BCCCC56F9031" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_A68428176FA4BAA1975EBCCCC56F815B" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_1A3B6C2F73AB8BBD50C4BCCCC56F9031" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_22936A9C131B3DFCB7DEBCCCC56FC09A" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_493BFDD17118A55D2211BCCCC56F4DB1" xlink:to="loc_us-gaap_DebtInstrumentAxis_22936A9C131B3DFCB7DEBCCCC56FC09A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_48C259C7BB591C0438BCBCCCC56F6203" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentAxis_22936A9C131B3DFCB7DEBCCCC56FC09A" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_48C259C7BB591C0438BCBCCCC56F6203" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_A2017CreditAgreementMember" xlink:label="loc_csgp_A2017CreditAgreementMember_4A401CAA55D60887B2D2BCCCC56F3B85" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_48C259C7BB591C0438BCBCCCC56F6203" xlink:to="loc_csgp_A2017CreditAgreementMember_4A401CAA55D60887B2D2BCCCC56F3B85" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VariableRateAxis" xlink:label="loc_us-gaap_VariableRateAxis_5FB24C4D07E141719B65BCCCC56F53CF" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_493BFDD17118A55D2211BCCCC56F4DB1" xlink:to="loc_us-gaap_VariableRateAxis_5FB24C4D07E141719B65BCCCC56F53CF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VariableRateDomain" xlink:label="loc_us-gaap_VariableRateDomain_BFD98D74C3638B5D79A3BCCCC56F3F3E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_VariableRateAxis_5FB24C4D07E141719B65BCCCC56F53CF" xlink:to="loc_us-gaap_VariableRateDomain_BFD98D74C3638B5D79A3BCCCC56F3F3E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FederalFundsEffectiveSwapRateMember" xlink:label="loc_us-gaap_FederalFundsEffectiveSwapRateMember_C08928F3B9AB7091B208BCCCC56FD414" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_VariableRateDomain_BFD98D74C3638B5D79A3BCCCC56F3F3E" xlink:to="loc_us-gaap_FederalFundsEffectiveSwapRateMember_C08928F3B9AB7091B208BCCCC56FD414" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LondonInterbankOfferedRateLIBORMember" xlink:label="loc_us-gaap_LondonInterbankOfferedRateLIBORMember_DFA531FE0BA0E24CA663BCCCC56F04B8" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_VariableRateDomain_BFD98D74C3638B5D79A3BCCCC56F3F3E" xlink:to="loc_us-gaap_LondonInterbankOfferedRateLIBORMember_DFA531FE0BA0E24CA663BCCCC56F04B8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentRedemptionPeriodAxis" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis_921C750CC6F79FEF0D16BCCCC56F6B41" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_493BFDD17118A55D2211BCCCC56F4DB1" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis_921C750CC6F79FEF0D16BCCCC56F6B41" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentRedemptionPeriodDomain" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_301C81F20E7075B62B1EBCCCC56F82A1" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis_921C750CC6F79FEF0D16BCCCC56F6B41" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_301C81F20E7075B62B1EBCCCC56F82A1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_FE267600C56E0A87B97CBCCCC56F2ECB" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_493BFDD17118A55D2211BCCCC56F4DB1" xlink:to="loc_us-gaap_RangeAxis_FE267600C56E0A87B97CBCCCC56F2ECB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_E46F573476C2CBA64B40BCCCC56FB416" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RangeAxis_FE267600C56E0A87B97CBCCCC56F2ECB" xlink:to="loc_us-gaap_RangeMember_E46F573476C2CBA64B40BCCCC56FB416" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_9DDA251A4C92EEDC93A2BCCCC56F81BF" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_493BFDD17118A55D2211BCCCC56F4DB1" xlink:to="loc_us-gaap_DebtInstrumentLineItems_9DDA251A4C92EEDC93A2BCCCC56F81BF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_CF96466877F1B0EC167ABCCCC56FDBCE" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_9DDA251A4C92EEDC93A2BCCCC56F81BF" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_CF96466877F1B0EC167ABCCCC56FDBCE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentTerm" xlink:label="loc_us-gaap_DebtInstrumentTerm_8FE99CDB0CA5F99EE9C0BCCCC56F1CEB" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_9DDA251A4C92EEDC93A2BCCCC56F81BF" xlink:to="loc_us-gaap_DebtInstrumentTerm_8FE99CDB0CA5F99EE9C0BCCCC56F1CEB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtIssuanceCostsLineOfCreditArrangementsGross" xlink:label="loc_us-gaap_DebtIssuanceCostsLineOfCreditArrangementsGross_FCF770F58CC7DFA635AFBCCCC57FC202" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_9DDA251A4C92EEDC93A2BCCCC56F81BF" xlink:to="loc_us-gaap_DebtIssuanceCostsLineOfCreditArrangementsGross_FCF770F58CC7DFA635AFBCCCC57FC202" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UnamortizedDebtIssuanceExpense" xlink:label="loc_us-gaap_UnamortizedDebtIssuanceExpense_847A820EC246A40A1F68BCCCC57F74A9" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_9DDA251A4C92EEDC93A2BCCCC56F81BF" xlink:to="loc_us-gaap_UnamortizedDebtIssuanceExpense_847A820EC246A40A1F68BCCCC57F74A9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_D58674594CAE9D1DF25CBCCCC57F7F1A" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_9DDA251A4C92EEDC93A2BCCCC56F81BF" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_D58674594CAE9D1DF25CBCCCC57F7F1A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_20679F5EA5F9C2F83F8EBCCCC57F3951" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_9DDA251A4C92EEDC93A2BCCCC56F81BF" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_20679F5EA5F9C2F83F8EBCCCC57F3951" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentInterestRateIncreaseDecrease" xlink:label="loc_us-gaap_DebtInstrumentInterestRateIncreaseDecrease_3748B867D0287DA3BD9CBCCCC57FEC73" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_9DDA251A4C92EEDC93A2BCCCC56F81BF" xlink:to="loc_us-gaap_DebtInstrumentInterestRateIncreaseDecrease_3748B867D0287DA3BD9CBCCCC57FEC73" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_LineOfCreditFacilityCovenantComplianceSecuredLeverageRatio" xlink:label="loc_csgp_LineOfCreditFacilityCovenantComplianceSecuredLeverageRatio_A71FF574E13DE57F32D1BCCCC57F4EB7" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_9DDA251A4C92EEDC93A2BCCCC56F81BF" xlink:to="loc_csgp_LineOfCreditFacilityCovenantComplianceSecuredLeverageRatio_A71FF574E13DE57F32D1BCCCC57F4EB7" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_LineOfCreditFacilityCovenantComplianceTotalLeverageRatio" xlink:label="loc_csgp_LineOfCreditFacilityCovenantComplianceTotalLeverageRatio_F666345E19D6BE5CEEBDBCCCC57F3522" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_9DDA251A4C92EEDC93A2BCCCC56F81BF" xlink:to="loc_csgp_LineOfCreditFacilityCovenantComplianceTotalLeverageRatio_F666345E19D6BE5CEEBDBCCCC57F3522" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_Maximumfirstliensecuredleverageratioaftereightquartersafterclosingdate" xlink:label="loc_csgp_Maximumfirstliensecuredleverageratioaftereightquartersafterclosingdate_B673FA3E7DC4CEB24F80BCCCC57F3E43" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtDisclosureAbstract_71291021B50FB0B4DB7ABCCCC56FA61A" xlink:to="loc_csgp_Maximumfirstliensecuredleverageratioaftereightquartersafterclosingdate_B673FA3E7DC4CEB24F80BCCCC57F3E43" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_MaximumTotalLeverageRatioAfterEightFiscalQuarters" xlink:label="loc_csgp_MaximumTotalLeverageRatioAfterEightFiscalQuarters_8BA3FE897B4603B15920BCCCC58086AB" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtDisclosureAbstract_71291021B50FB0B4DB7ABCCCC56FA61A" xlink:to="loc_csgp_MaximumTotalLeverageRatioAfterEightFiscalQuarters_8BA3FE897B4603B15920BCCCC58086AB" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/LongTermDebtDetailsInterestExpenseAndAmortizationOfDebtIssuanceCosts" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtDisclosureAbstract" xlink:label="loc_us-gaap_DebtDisclosureAbstract_AE25906D21872C1B5501BDDBDE8E821A" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_031E1C54B8ECDD26171EBDDBDE8EC132" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtDisclosureAbstract_AE25906D21872C1B5501BDDBDE8E821A" xlink:to="loc_us-gaap_DebtInstrumentTable_031E1C54B8ECDD26171EBDDBDE8EC132" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_548AA652F426AA1526FBBDDBDE8E5C96" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_031E1C54B8ECDD26171EBDDBDE8EC132" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_548AA652F426AA1526FBBDDBDE8E5C96" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_3E3F41121AA29C4B2F27BDDBDE8E94B0" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_548AA652F426AA1526FBBDDBDE8E5C96" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_3E3F41121AA29C4B2F27BDDBDE8E94B0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevolvingCreditFacilityMember" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_767C4E2E685C248B70FABDDBDE8E81BA" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_3E3F41121AA29C4B2F27BDDBDE8E94B0" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_767C4E2E685C248B70FABDDBDE8E81BA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_6BAC85C86B2A2954F67BBDDBDE8E0436" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_031E1C54B8ECDD26171EBDDBDE8EC132" xlink:to="loc_us-gaap_DebtInstrumentLineItems_6BAC85C86B2A2954F67BBDDBDE8E0436" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCredit" xlink:label="loc_us-gaap_LineOfCredit_E1D6DCE27A69096045BBBDDBDE8F3D06" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6BAC85C86B2A2954F67BBDDBDE8E0436" xlink:to="loc_us-gaap_LineOfCredit_E1D6DCE27A69096045BBBDDBDE8F3D06" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InterestExpenseDebt" xlink:label="loc_us-gaap_InterestExpenseDebt_1DFF7DC700AABF253E7FBDDBDE909B7D" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6BAC85C86B2A2954F67BBDDBDE8E0436" xlink:to="loc_us-gaap_InterestExpenseDebt_1DFF7DC700AABF253E7FBDDBDE909B7D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="loc_us-gaap_AmortizationOfFinancingCosts_0EDEA18DEF3B2BC0B460BDDBDE90C4A8" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6BAC85C86B2A2954F67BBDDBDE8E0436" xlink:to="loc_us-gaap_AmortizationOfFinancingCosts_0EDEA18DEF3B2BC0B460BDDBDE90C4A8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InterestPaid" xlink:label="loc_us-gaap_InterestPaid_F1F4E396416E39A427A6BDDBDE901D86" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6BAC85C86B2A2954F67BBDDBDE8E0436" xlink:to="loc_us-gaap_InterestPaid_F1F4E396416E39A427A6BDDBDE901D86" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredFinanceCostsNet" xlink:label="loc_us-gaap_DeferredFinanceCostsNet_763D5ECA032ADAA078FABDDBDE9021AF" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6BAC85C86B2A2954F67BBDDBDE8E0436" xlink:to="loc_us-gaap_DeferredFinanceCostsNet_763D5ECA032ADAA078FABDDBDE9021AF" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/LongTermDebtTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongtermDebtCurrentAndNoncurrentAbstract" xlink:label="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_A68BDF2673DE0664E3ECBAB943FFB86F" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfDebtInstrumentsTextBlock" xlink:label="loc_us-gaap_ScheduleOfDebtInstrumentsTextBlock_E428095F785A43557AFFBAB944005B31" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_A68BDF2673DE0664E3ECBAB943FFB86F" xlink:to="loc_us-gaap_ScheduleOfDebtInstrumentsTextBlock_E428095F785A43557AFFBAB944005B31" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/NetIncomeLossPerShare" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaap_EarningsPerShareAbstract_2F9338CB42A85446C2E7DA91C4D35403" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareTextBlock" xlink:label="loc_us-gaap_EarningsPerShareTextBlock_AF1F2AE1CCBB513AB8E0DA91C4D4DCBE" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EarningsPerShareAbstract_2F9338CB42A85446C2E7DA91C4D35403" xlink:to="loc_us-gaap_EarningsPerShareTextBlock_AF1F2AE1CCBB513AB8E0DA91C4D4DCBE" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/NetIncomeLossPerShareDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaap_EarningsPerShareAbstract_C548B0BF51F2B092068EBAB9432CD4B3" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareReconciliationAbstract" xlink:label="loc_us-gaap_EarningsPerShareReconciliationAbstract_9571642B11C4CFB046E5BAB9432C0123" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EarningsPerShareAbstract_C548B0BF51F2B092068EBAB9432CD4B3" xlink:to="loc_us-gaap_EarningsPerShareReconciliationAbstract_9571642B11C4CFB046E5BAB9432C0123" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_404C9671BD0319DD152FBAB9432CD58F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EarningsPerShareReconciliationAbstract_9571642B11C4CFB046E5BAB9432C0123" xlink:to="loc_us-gaap_NetIncomeLoss_404C9671BD0319DD152FBAB9432CD58F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_ED5B37B92876CF2173C5BAB9432C55F4" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EarningsPerShareAbstract_C548B0BF51F2B092068EBAB9432CD4B3" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_ED5B37B92876CF2173C5BAB9432C55F4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_140B53E0B3DF2F4FBF01BAB9432D3F12" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_ED5B37B92876CF2173C5BAB9432C55F4" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_140B53E0B3DF2F4FBF01BAB9432D3F12" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DilutiveSecuritiesAbstract" xlink:label="loc_us-gaap_DilutiveSecuritiesAbstract_6DAD3969A60C4D0F8387BAB9432D2E21" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EarningsPerShareAbstract_C548B0BF51F2B092068EBAB9432CD4B3" xlink:to="loc_us-gaap_DilutiveSecuritiesAbstract_6DAD3969A60C4D0F8387BAB9432D2E21" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_6C8E45F1FF42BC86A6E5BAB9432D3E91" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DilutiveSecuritiesAbstract_6DAD3969A60C4D0F8387BAB9432D2E21" xlink:to="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_6C8E45F1FF42BC86A6E5BAB9432D3E91" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_0426162D373104A50D76BAB9432D9FF4" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DilutiveSecuritiesAbstract_6DAD3969A60C4D0F8387BAB9432D2E21" xlink:to="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_0426162D373104A50D76BAB9432D9FF4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareBasic" xlink:label="loc_us-gaap_EarningsPerShareBasic_47D5CE539F35E3739FE6BAB9432D4079" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EarningsPerShareAbstract_C548B0BF51F2B092068EBAB9432CD4B3" xlink:to="loc_us-gaap_EarningsPerShareBasic_47D5CE539F35E3739FE6BAB9432D4079" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareDiluted" xlink:label="loc_us-gaap_EarningsPerShareDiluted_296D1E91B7AE453E4CC2BAB9432D2000" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EarningsPerShareAbstract_C548B0BF51F2B092068EBAB9432CD4B3" xlink:to="loc_us-gaap_EarningsPerShareDiluted_296D1E91B7AE453E4CC2BAB9432D2000" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_71A7EEBD4C68C814C3E6BAB9432D30A5" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EarningsPerShareAbstract_C548B0BF51F2B092068EBAB9432CD4B3" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_71A7EEBD4C68C814C3E6BAB9432D30A5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_1D60B1EB96D494A8603ABAB9432D88E8" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_71A7EEBD4C68C814C3E6BAB9432D30A5" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_1D60B1EB96D494A8603ABAB9432D88E8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AntidilutiveSecuritiesNameDomain" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_F6EAACABD7075D86D992BAB9432D0B49" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_1D60B1EB96D494A8603ABAB9432D88E8" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_F6EAACABD7075D86D992BAB9432D0B49" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="loc_us-gaap_EmployeeStockOptionMember_B2C2B2063935D716B541BAB9432DE1BE" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_F6EAACABD7075D86D992BAB9432D0B49" xlink:to="loc_us-gaap_EmployeeStockOptionMember_B2C2B2063935D716B541BAB9432DE1BE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedStockMember" xlink:label="loc_us-gaap_RestrictedStockMember_E05D58BCFA42F4FE8451BAB9432D805A" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_F6EAACABD7075D86D992BAB9432D0B49" xlink:to="loc_us-gaap_RestrictedStockMember_E05D58BCFA42F4FE8451BAB9432D805A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedStockUnitsRSUMember" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_04AC34CCED3DBA68D790BAB9432D4A01" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_F6EAACABD7075D86D992BAB9432D0B49" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_04AC34CCED3DBA68D790BAB9432D4A01" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_C15BB2E3528621B88B67BAB9432D2FD8" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_71A7EEBD4C68C814C3E6BAB9432D30A5" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_C15BB2E3528621B88B67BAB9432D2FD8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_09E0C22488BBC69F2C7BBAB9432DF606" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_C15BB2E3528621B88B67BAB9432D2FD8" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_09E0C22488BBC69F2C7BBAB9432DF606" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/NetIncomeLossPerSharePolicies" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaap_EarningsPerShareAbstract_C33157A629030981B4A1DA91C5278496" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerSharePolicyTextBlock" xlink:label="loc_us-gaap_EarningsPerSharePolicyTextBlock_ADCD5F8F9F3E04FE2B88DA91C527FC06" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EarningsPerShareAbstract_C33157A629030981B4A1DA91C5278496" xlink:to="loc_us-gaap_EarningsPerSharePolicyTextBlock_ADCD5F8F9F3E04FE2B88DA91C527FC06" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/NetIncomeLossPerShareTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaap_EarningsPerShareAbstract_CCDA67A805ED1E4C08BDDA91C3B0A9D7" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_C4C6A6D6854FE59760DFDA91C3B0677A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EarningsPerShareAbstract_CCDA67A805ED1E4C08BDDA91C3B0A9D7" xlink:to="loc_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_C4C6A6D6854FE59760DFDA91C3B0677A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_DF24C6D19E35EB4F951BDA91C3B0766B" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EarningsPerShareAbstract_CCDA67A805ED1E4C08BDDA91C3B0A9D7" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_DF24C6D19E35EB4F951BDA91C3B0766B" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/Organization" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:label="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_FC169E7926111563DA62DA91C4F889E0" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NatureOfOperations" xlink:label="loc_us-gaap_NatureOfOperations_C894C0D85DA2136B8323DA91C4F9438C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_FC169E7926111563DA62DA91C4F889E0" xlink:to="loc_us-gaap_NatureOfOperations_C894C0D85DA2136B8323DA91C4F9438C" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/OrganizationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:label="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_09C915F0C22501661068DA91C4CB027B" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NumberOfOperatingSegments" xlink:label="loc_us-gaap_NumberOfOperatingSegments_9845E6456533C351B1EFDA91C4CBAB03" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_09C915F0C22501661068DA91C4CB027B" xlink:to="loc_us-gaap_NumberOfOperatingSegments_9845E6456533C351B1EFDA91C4CBAB03" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_SubscriptionBasedLicensingAgreementMinimumTermYears" xlink:label="loc_csgp_SubscriptionBasedLicensingAgreementMinimumTermYears_D73D62916AAEA0F538D4DA91C4CCF69C" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_09C915F0C22501661068DA91C4CB027B" xlink:to="loc_csgp_SubscriptionBasedLicensingAgreementMinimumTermYears_D73D62916AAEA0F538D4DA91C4CCF69C" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/PropertyAndEquipment" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAbstract" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAbstract_AE70B46FBF1C12550A32DA91C4D5D8EA" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_DBF5E862649BC19A1923DA91C4D5A98A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAbstract_AE70B46FBF1C12550A32DA91C4D5D8EA" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_DBF5E862649BC19A1923DA91C4D5A98A" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/PropertyAndEquipmentDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAbstract" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAbstract_E74796EABAD0D82F5C29E4782736CC9B" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_C9BCAE87BEDFC2E80C40E4782737C129" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAbstract_E74796EABAD0D82F5C29E4782736CC9B" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_C9BCAE87BEDFC2E80C40E4782737C129" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_E38578F8131332290B5CE4782737FF82" xlink:type="locator" />
    <link:presentationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_C9BCAE87BEDFC2E80C40E4782737C129" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_E38578F8131332290B5CE4782737FF82" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_5DE56ED0D8847BC679A8E47827376975" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_E38578F8131332290B5CE4782737FF82" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_5DE56ED0D8847BC679A8E47827376975" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LeaseholdImprovementsMember" xlink:label="loc_us-gaap_LeaseholdImprovementsMember_3320AC3B67715E1EAB96E478273738DF" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_5DE56ED0D8847BC679A8E47827376975" xlink:to="loc_us-gaap_LeaseholdImprovementsMember_3320AC3B67715E1EAB96E478273738DF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FurnitureAndFixturesMember" xlink:label="loc_us-gaap_FurnitureAndFixturesMember_F9C881A7946A843BD734E4782737035C" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_5DE56ED0D8847BC679A8E47827376975" xlink:to="loc_us-gaap_FurnitureAndFixturesMember_F9C881A7946A843BD734E4782737035C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ComputerEquipmentMember" xlink:label="loc_us-gaap_ComputerEquipmentMember_8FBEFE755AA2711D31EFE4782737CE7C" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_5DE56ED0D8847BC679A8E47827376975" xlink:to="loc_us-gaap_ComputerEquipmentMember_8FBEFE755AA2711D31EFE4782737CE7C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentLineItems" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_5C90C80C0B8FDD71205BE4782737D961" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_C9BCAE87BEDFC2E80C40E4782737C129" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentLineItems_5C90C80C0B8FDD71205BE4782737D961" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentGross" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross_F056F8C777BBFAA6B003E4782737DB61" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_5C90C80C0B8FDD71205BE4782737D961" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentGross_F056F8C777BBFAA6B003E4782737DB61" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_F482764ABAC7B9A8586AE4782737C9F3" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_5C90C80C0B8FDD71205BE4782737D961" xlink:to="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_F482764ABAC7B9A8586AE4782737C9F3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_06F2642290FF29890146E4782737DE86" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_5C90C80C0B8FDD71205BE4782737D961" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_06F2642290FF29890146E4782737DE86" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Depreciation" xlink:label="loc_us-gaap_Depreciation_287983DBF3F378521575E47827375F21" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_5C90C80C0B8FDD71205BE4782737D961" xlink:to="loc_us-gaap_Depreciation_287983DBF3F378521575E47827375F21" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/PropertyAndEquipmentTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAbstract" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAbstract_10A04D690DC130EBEF40DA91C5125939" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTextBlock" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTextBlock_9F09B9D08AD6FD495346DA91C51295E7" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAbstract_10A04D690DC130EBEF40DA91C5125939" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTextBlock_9F09B9D08AD6FD495346DA91C51295E7" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/QuarterlyResults" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SelectedQuarterlyFinancialInformationAbstract" xlink:label="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_04027A4ED67648907B6EBF392B8DD12E" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_QuarterlyFinancialInformationTextBlock" xlink:label="loc_us-gaap_QuarterlyFinancialInformationTextBlock_7B45D92108D24CD29C47BF3B607BD497" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_04027A4ED67648907B6EBF392B8DD12E" xlink:to="loc_us-gaap_QuarterlyFinancialInformationTextBlock_7B45D92108D24CD29C47BF3B607BD497" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/QuarterlyResultsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SelectedQuarterlyFinancialInformationAbstract" xlink:label="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_8D8EB975B390C4FA3382BF3927E48921" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_C3264771D6B392479282BF3FCFBA6DF6" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_8D8EB975B390C4FA3382BF3927E48921" xlink:to="loc_us-gaap_Revenues_C3264771D6B392479282BF3FCFBA6DF6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CostOfRevenue" xlink:label="loc_us-gaap_CostOfRevenue_56C587E5F0AD11A5623FBF3FE2563D68" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_8D8EB975B390C4FA3382BF3927E48921" xlink:to="loc_us-gaap_CostOfRevenue_56C587E5F0AD11A5623FBF3FE2563D68" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GrossProfit" xlink:label="loc_us-gaap_GrossProfit_03BCB13042C5D8F637BBBF3FF75D9B79" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_8D8EB975B390C4FA3382BF3927E48921" xlink:to="loc_us-gaap_GrossProfit_03BCB13042C5D8F637BBBF3FF75D9B79" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingExpenses" xlink:label="loc_us-gaap_OperatingExpenses_9E743EE63B98CCBFB12CBF401AA813C2" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_8D8EB975B390C4FA3382BF3927E48921" xlink:to="loc_us-gaap_OperatingExpenses_9E743EE63B98CCBFB12CBF401AA813C2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_025406139C0EE239D3BABF402F5BDF48" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_8D8EB975B390C4FA3382BF3927E48921" xlink:to="loc_us-gaap_OperatingIncomeLoss_025406139C0EE239D3BABF402F5BDF48" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherNonoperatingIncome" xlink:label="loc_us-gaap_OtherNonoperatingIncome_474FC146887DC0735E1ABF404483885E" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_8D8EB975B390C4FA3382BF3927E48921" xlink:to="loc_us-gaap_OtherNonoperatingIncome_474FC146887DC0735E1ABF404483885E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaap_InterestExpense_147493470CA7B85D2234BF405AC8AA39" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_8D8EB975B390C4FA3382BF3927E48921" xlink:to="loc_us-gaap_InterestExpense_147493470CA7B85D2234BF405AC8AA39" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_C4379538ABACC73474AABF408B7A26BD" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_8D8EB975B390C4FA3382BF3927E48921" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_C4379538ABACC73474AABF408B7A26BD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_9B757D63401AB63FDFBBBF40A02F544A" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_8D8EB975B390C4FA3382BF3927E48921" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_9B757D63401AB63FDFBBBF40A02F544A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_49F615CA7A4926A318A8BF40B4D85263" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_8D8EB975B390C4FA3382BF3927E48921" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_49F615CA7A4926A318A8BF40B4D85263" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_99B9CF64CAA3486F9026BF40C9A7EFB8" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_8D8EB975B390C4FA3382BF3927E48921" xlink:to="loc_us-gaap_NetIncomeLoss_99B9CF64CAA3486F9026BF40C9A7EFB8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareBasic" xlink:label="loc_us-gaap_EarningsPerShareBasic_51528D866EDE0FDC8998BF40F0116834" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_8D8EB975B390C4FA3382BF3927E48921" xlink:to="loc_us-gaap_EarningsPerShareBasic_51528D866EDE0FDC8998BF40F0116834" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareDiluted" xlink:label="loc_us-gaap_EarningsPerShareDiluted_47A795D17B0246A88632BF4104927005" xlink:type="locator" />
    <link:presentationArc order="13" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_8D8EB975B390C4FA3382BF3927E48921" xlink:to="loc_us-gaap_EarningsPerShareDiluted_47A795D17B0246A88632BF4104927005" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/QuarterlyResultsTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SelectedQuarterlyFinancialInformationAbstract" xlink:label="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_9D41849133E3DF01273EBF392884ED72" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock_136073C93C898C28BD03BF3BF8D03AF5" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SelectedQuarterlyFinancialInformationAbstract_9D41849133E3DF01273EBF392884ED72" xlink:to="loc_us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock_136073C93C898C28BD03BF3BF8D03AF5" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/ScheduleIiValuationAndQualifyingAccounts" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ValuationAndQualifyingAccountsAbstract" xlink:label="loc_us-gaap_ValuationAndQualifyingAccountsAbstract_18C263FEAB61434491F3DA91C3B184D1" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfValuationAndQualifyingAccountsDisclosureTextBlock" xlink:label="loc_us-gaap_ScheduleOfValuationAndQualifyingAccountsDisclosureTextBlock_6AD0DBB079537E4BE595DA91C3B1AE6E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ValuationAndQualifyingAccountsAbstract_18C263FEAB61434491F3DA91C3B184D1" xlink:to="loc_us-gaap_ScheduleOfValuationAndQualifyingAccountsDisclosureTextBlock_6AD0DBB079537E4BE595DA91C3B1AE6E" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/ScheduleIiValuationAndQualifyingAccountsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ValuationAndQualifyingAccountsAbstract" xlink:label="loc_us-gaap_ValuationAndQualifyingAccountsAbstract_6B510F9D4484156B4BBBDA91C47DB3A7" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ValuationAllowancesAndReservesBalance" xlink:label="loc_us-gaap_ValuationAllowancesAndReservesBalance_1EA863F4E6EEEFB4493BDA91C47D1FE2" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ValuationAndQualifyingAccountsAbstract_6B510F9D4484156B4BBBDA91C47DB3A7" xlink:to="loc_us-gaap_ValuationAllowancesAndReservesBalance_1EA863F4E6EEEFB4493BDA91C47D1FE2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense" xlink:label="loc_us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense_FA97919D601CD41A02F5DA91C47D4AD5" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ValuationAndQualifyingAccountsAbstract_6B510F9D4484156B4BBBDA91C47DB3A7" xlink:to="loc_us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense_FA97919D601CD41A02F5DA91C47D4AD5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts" xlink:label="loc_us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts_1DAFE16705B81D833402DA91C47DCF0C" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ValuationAndQualifyingAccountsAbstract_6B510F9D4484156B4BBBDA91C47DB3A7" xlink:to="loc_us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts_1DAFE16705B81D833402DA91C47DCF0C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ValuationAllowancesAndReservesDeductions" xlink:label="loc_us-gaap_ValuationAllowancesAndReservesDeductions_18B1BE195DB4E6EB126EDA91C47DE83A" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ValuationAndQualifyingAccountsAbstract_6B510F9D4484156B4BBBDA91C47DB3A7" xlink:to="loc_us-gaap_ValuationAllowancesAndReservesDeductions_18B1BE195DB4E6EB126EDA91C47DE83A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ValuationAllowancesAndReservesBalance" xlink:label="loc_us-gaap_ValuationAllowancesAndReservesBalance_5DA39673BB5E0C7C8E6FDA91C47DBAAB" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ValuationAndQualifyingAccountsAbstract_6B510F9D4484156B4BBBDA91C47DB3A7" xlink:to="loc_us-gaap_ValuationAllowancesAndReservesBalance_5DA39673BB5E0C7C8E6FDA91C47DBAAB" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SegmentReporting" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentReportingAbstract" xlink:label="loc_us-gaap_SegmentReportingAbstract_05B48F8CC0AED94B7015DA91C531DCD1" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentReportingDisclosureTextBlock" xlink:label="loc_us-gaap_SegmentReportingDisclosureTextBlock_5E73DD645C88DF10E4B3DA91C531D97E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingAbstract_05B48F8CC0AED94B7015DA91C531DCD1" xlink:to="loc_us-gaap_SegmentReportingDisclosureTextBlock_5E73DD645C88DF10E4B3DA91C531D97E" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SegmentReportingAssetsAndLiabilitiesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentReportingAbstract" xlink:label="loc_us-gaap_SegmentReportingAbstract_45E2F09A707C12FB021FBDDBDE0100EF" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_A32231A5E7C83C714B6ABDDBDE017DA7" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingAbstract_45E2F09A707C12FB021FBDDBDE0100EF" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_A32231A5E7C83C714B6ABDDBDE017DA7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConsolidationItemsAxis" xlink:label="loc_us-gaap_ConsolidationItemsAxis_DCDC1DA86A504E7E8271BDDBDE01A751" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_A32231A5E7C83C714B6ABDDBDE017DA7" xlink:to="loc_us-gaap_ConsolidationItemsAxis_DCDC1DA86A504E7E8271BDDBDE01A751" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConsolidationItemsDomain" xlink:label="loc_us-gaap_ConsolidationItemsDomain_ADF9E874C0E17F21FBDCBDDBDE011922" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ConsolidationItemsAxis_DCDC1DA86A504E7E8271BDDBDE01A751" xlink:to="loc_us-gaap_ConsolidationItemsDomain_ADF9E874C0E17F21FBDCBDDBDE011922" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingSegmentsMember" xlink:label="loc_us-gaap_OperatingSegmentsMember_90B020A97E7289DABB49BDDBDE011497" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ConsolidationItemsDomain_ADF9E874C0E17F21FBDCBDDBDE011922" xlink:to="loc_us-gaap_OperatingSegmentsMember_90B020A97E7289DABB49BDDBDE011497" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IntersegmentEliminationMember" xlink:label="loc_us-gaap_IntersegmentEliminationMember_0F6353B9E067D9C8DAEABDDBDE02203B" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ConsolidationItemsDomain_ADF9E874C0E17F21FBDCBDDBDE011922" xlink:to="loc_us-gaap_IntersegmentEliminationMember_0F6353B9E067D9C8DAEABDDBDE02203B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_182490481C9E4C113BF9BDDBDE02169B" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_A32231A5E7C83C714B6ABDDBDE017DA7" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_182490481C9E4C113BF9BDDBDE02169B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_B5C23C9FA150614F22D6BDDBDE02DBBD" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_182490481C9E4C113BF9BDDBDE02169B" xlink:to="loc_us-gaap_SegmentDomain_B5C23C9FA150614F22D6BDDBDE02DBBD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NorthAmericaMember" xlink:label="loc_us-gaap_NorthAmericaMember_B4958F36E2FC951B5B9EBDDBDE0257A6" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentDomain_B5C23C9FA150614F22D6BDDBDE02DBBD" xlink:to="loc_us-gaap_NorthAmericaMember_B4958F36E2FC951B5B9EBDDBDE0257A6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EuropeMember" xlink:label="loc_us-gaap_EuropeMember_279692A06AA3DD79E64CBDDBDE02764E" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentDomain_B5C23C9FA150614F22D6BDDBDE02DBBD" xlink:to="loc_us-gaap_EuropeMember_279692A06AA3DD79E64CBDDBDE02764E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_D92FEBDD4B2EC90AFB6CBDDBDE022BEF" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_A32231A5E7C83C714B6ABDDBDE017DA7" xlink:to="loc_us-gaap_SegmentReportingInformationLineItems_D92FEBDD4B2EC90AFB6CBDDBDE022BEF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_5EE917B5BF17A6487876BDDBDE02EDB7" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_D92FEBDD4B2EC90AFB6CBDDBDE022BEF" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_5EE917B5BF17A6487876BDDBDE02EDB7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_AF1795379D12C2C9DB5CBDDBDE023D0F" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_D92FEBDD4B2EC90AFB6CBDDBDE022BEF" xlink:to="loc_us-gaap_Goodwill_AF1795379D12C2C9DB5CBDDBDE023D0F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ReconciliationFromSegmentTotalsToConsolidatedAbstract" xlink:label="loc_us-gaap_ReconciliationFromSegmentTotalsToConsolidatedAbstract_690D1896233672E26285BDDBDE047571" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_D92FEBDD4B2EC90AFB6CBDDBDE022BEF" xlink:to="loc_us-gaap_ReconciliationFromSegmentTotalsToConsolidatedAbstract_690D1896233672E26285BDDBDE047571" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Assets" xlink:label="loc_us-gaap_Assets_CE3373ADB8C662312C5BBDDBDE041618" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationFromSegmentTotalsToConsolidatedAbstract_690D1896233672E26285BDDBDE047571" xlink:to="loc_us-gaap_Assets_CE3373ADB8C662312C5BBDDBDE041618" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentReportingInformationAdditionalInformationAbstract" xlink:label="loc_us-gaap_SegmentReportingInformationAdditionalInformationAbstract_552B82E200A7DCA1B54EBDDBDE04304A" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_D92FEBDD4B2EC90AFB6CBDDBDE022BEF" xlink:to="loc_us-gaap_SegmentReportingInformationAdditionalInformationAbstract_552B82E200A7DCA1B54EBDDBDE04304A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaap_Liabilities_3C66BDFEF9D9554BE5E8BDDBDE0406BE" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingInformationAdditionalInformationAbstract_552B82E200A7DCA1B54EBDDBDE04304A" xlink:to="loc_us-gaap_Liabilities_3C66BDFEF9D9554BE5E8BDDBDE0406BE" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SegmentReportingDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentReportingAbstract" xlink:label="loc_us-gaap_SegmentReportingAbstract_DA10C54C957582F8C00ABF4EF40EBF5A" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_678B9F70195F9F7A95CABF4EF40EDA02" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingAbstract_DA10C54C957582F8C00ABF4EF40EBF5A" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_678B9F70195F9F7A95CABF4EF40EDA02" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConsolidationItemsAxis" xlink:label="loc_us-gaap_ConsolidationItemsAxis_68F1EFBC037CEEFDD220BF4EF40EC913" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_678B9F70195F9F7A95CABF4EF40EDA02" xlink:to="loc_us-gaap_ConsolidationItemsAxis_68F1EFBC037CEEFDD220BF4EF40EC913" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConsolidationItemsDomain" xlink:label="loc_us-gaap_ConsolidationItemsDomain_B772BE1ADED0A2B16823BF4EF40EC854" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ConsolidationItemsAxis_68F1EFBC037CEEFDD220BF4EF40EC913" xlink:to="loc_us-gaap_ConsolidationItemsDomain_B772BE1ADED0A2B16823BF4EF40EC854" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingSegmentsMember" xlink:label="loc_us-gaap_OperatingSegmentsMember_F84AD9442B27CDC3455ABF4EF40E0548" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ConsolidationItemsDomain_B772BE1ADED0A2B16823BF4EF40EC854" xlink:to="loc_us-gaap_OperatingSegmentsMember_F84AD9442B27CDC3455ABF4EF40E0548" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MaterialReconcilingItemsMember" xlink:label="loc_us-gaap_MaterialReconcilingItemsMember_7B080DA4C3D05C566412BF4EF40E3888" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ConsolidationItemsDomain_B772BE1ADED0A2B16823BF4EF40EC854" xlink:to="loc_us-gaap_MaterialReconcilingItemsMember_7B080DA4C3D05C566412BF4EF40E3888" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IntersegmentEliminationMember" xlink:label="loc_us-gaap_IntersegmentEliminationMember_7EED8BDC43AD078800EEBF4EF40E9438" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ConsolidationItemsDomain_B772BE1ADED0A2B16823BF4EF40EC854" xlink:to="loc_us-gaap_IntersegmentEliminationMember_7EED8BDC43AD078800EEBF4EF40E9438" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_B785B062BD7D74C41D80BF4EF40EF633" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_678B9F70195F9F7A95CABF4EF40EDA02" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_B785B062BD7D74C41D80BF4EF40EF633" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_D8505923C9A0A15F226FBF4EF40E1D56" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_B785B062BD7D74C41D80BF4EF40EF633" xlink:to="loc_us-gaap_SegmentDomain_D8505923C9A0A15F226FBF4EF40E1D56" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NorthAmericaMember" xlink:label="loc_us-gaap_NorthAmericaMember_56E404C7ACA8F7FAF9C8BF4EF40EA404" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentDomain_D8505923C9A0A15F226FBF4EF40E1D56" xlink:to="loc_us-gaap_NorthAmericaMember_56E404C7ACA8F7FAF9C8BF4EF40EA404" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EuropeMember" xlink:label="loc_us-gaap_EuropeMember_4AED24491275C6B3601BBF4EF40EF554" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentDomain_D8505923C9A0A15F226FBF4EF40E1D56" xlink:to="loc_us-gaap_EuropeMember_4AED24491275C6B3601BBF4EF40EF554" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsegmentsAxis" xlink:label="loc_us-gaap_SubsegmentsAxis_89AFBC485D52AC643E87BF4EF40FEA36" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_678B9F70195F9F7A95CABF4EF40EDA02" xlink:to="loc_us-gaap_SubsegmentsAxis_89AFBC485D52AC643E87BF4EF40FEA36" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsegmentsDomain" xlink:label="loc_us-gaap_SubsegmentsDomain_F7DA6B25796325DE1484BF4EF40F9F9A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsegmentsAxis_89AFBC485D52AC643E87BF4EF40FEA36" xlink:to="loc_us-gaap_SubsegmentsDomain_F7DA6B25796325DE1484BF4EF40F9F9A" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_ExternalCustomersMember" xlink:label="loc_csgp_ExternalCustomersMember_F9E8060C7A25A540C75ABF4EF40FEC74" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsegmentsDomain_F7DA6B25796325DE1484BF4EF40F9F9A" xlink:to="loc_csgp_ExternalCustomersMember_F9E8060C7A25A540C75ABF4EF40FEC74" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_CE92C97704CF3FF4783DBF4EF40FD12F" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_678B9F70195F9F7A95CABF4EF40EDA02" xlink:to="loc_us-gaap_SegmentReportingInformationLineItems_CE92C97704CF3FF4783DBF4EF40FD12F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NumberOfOperatingSegments" xlink:label="loc_us-gaap_NumberOfOperatingSegments_FCFAF2950D8C0B682337BF4EF40F07FC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_CE92C97704CF3FF4783DBF4EF40FD12F" xlink:to="loc_us-gaap_NumberOfOperatingSegments_FCFAF2950D8C0B682337BF4EF40F07FC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentReportingInformationRevenueAbstract" xlink:label="loc_us-gaap_SegmentReportingInformationRevenueAbstract_61F23B08BAF4C2DA199DBF4EF40F6C60" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_CE92C97704CF3FF4783DBF4EF40FD12F" xlink:to="loc_us-gaap_SegmentReportingInformationRevenueAbstract_61F23B08BAF4C2DA199DBF4EF40F6C60" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_4C176692F7438655DBC5BF4EF40FA052" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingInformationRevenueAbstract_61F23B08BAF4C2DA199DBF4EF40F6C60" xlink:to="loc_us-gaap_Revenues_4C176692F7438655DBC5BF4EF40FA052" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedAbstract" xlink:label="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedAbstract_7D6D7700ED5393408A7EBF4EF40F5D00" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_CE92C97704CF3FF4783DBF4EF40FD12F" xlink:to="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedAbstract_7D6D7700ED5393408A7EBF4EF40F5D00" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_86293E5A11032B3BC945BF4EF40F46C7" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedAbstract_7D6D7700ED5393408A7EBF4EF40F5D00" xlink:to="loc_us-gaap_NetIncomeLoss_86293E5A11032B3BC945BF4EF40F46C7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CostOfGoodsSoldAmortization" xlink:label="loc_us-gaap_CostOfGoodsSoldAmortization_28D3425D021861A3E7DEBF4EF40FAA30" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedAbstract_7D6D7700ED5393408A7EBF4EF40F5D00" xlink:to="loc_us-gaap_CostOfGoodsSoldAmortization_28D3425D021861A3E7DEBF4EF40FAA30" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_AmortizationOfIntangibleAssetsNetOfAdjustments" xlink:label="loc_csgp_AmortizationOfIntangibleAssetsNetOfAdjustments_699325F3B197B57FBD8EBF500E36979D" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedAbstract_7D6D7700ED5393408A7EBF4EF40F5D00" xlink:to="loc_csgp_AmortizationOfIntangibleAssetsNetOfAdjustments_699325F3B197B57FBD8EBF500E36979D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherDepreciationAndAmortization" xlink:label="loc_us-gaap_OtherDepreciationAndAmortization_A060861EFFBB523A90C1BF4EF40FE1A5" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedAbstract_7D6D7700ED5393408A7EBF4EF40F5D00" xlink:to="loc_us-gaap_OtherDepreciationAndAmortization_A060861EFFBB523A90C1BF4EF40FE1A5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherNonoperatingIncome" xlink:label="loc_us-gaap_OtherNonoperatingIncome_60211C60877EB8512D2EBF4EF40F0A3C" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedAbstract_7D6D7700ED5393408A7EBF4EF40F5D00" xlink:to="loc_us-gaap_OtherNonoperatingIncome_60211C60877EB8512D2EBF4EF40F0A3C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaap_InterestExpense_B224EB74F35E9589B8F9BF4EF40F3947" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedAbstract_7D6D7700ED5393408A7EBF4EF40F5D00" xlink:to="loc_us-gaap_InterestExpense_B224EB74F35E9589B8F9BF4EF40F3947" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_96A7D0A01ADBCB95FB49BF4EF40FDE29" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedAbstract_7D6D7700ED5393408A7EBF4EF40F5D00" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_96A7D0A01ADBCB95FB49BF4EF40FDE29" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_1C1B3932339E8631FBF2BF4EF4109218" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedAbstract_7D6D7700ED5393408A7EBF4EF40F5D00" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_1C1B3932339E8631FBF2BF4EF4109218" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_NetincomelossbeforeinterestincometaxesdepreciationandamortizationEBITDA" xlink:label="loc_csgp_NetincomelossbeforeinterestincometaxesdepreciationandamortizationEBITDA_823DBA5E9E1D7BE441EEBF4EF410FCB0" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedAbstract_7D6D7700ED5393408A7EBF4EF40F5D00" xlink:to="loc_csgp_NetincomelossbeforeinterestincometaxesdepreciationandamortizationEBITDA_823DBA5E9E1D7BE441EEBF4EF410FCB0" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_NetincomelossbeforeinterestandotherincomeexpenseincometaxesdepreciationandamortizationEBITDA" xlink:label="loc_csgp_NetincomelossbeforeinterestandotherincomeexpenseincometaxesdepreciationandamortizationEBITDA_B6443806B67B7F1D92D8BF4EF4103A04" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedAbstract_7D6D7700ED5393408A7EBF4EF40F5D00" xlink:to="loc_csgp_NetincomelossbeforeinterestandotherincomeexpenseincometaxesdepreciationandamortizationEBITDA_B6443806B67B7F1D92D8BF4EF4103A04" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SegmentReportingSegmentReportingRevenuesByServicesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentReportingAbstract" xlink:label="loc_us-gaap_SegmentReportingAbstract_AFD825B7E588E665E6CCE50EBB86E201" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable" xlink:label="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_978D54DDCBB91AD9CAB8E50EBB869122" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingAbstract_AFD825B7E588E665E6CCE50EBB86E201" xlink:to="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_978D54DDCBB91AD9CAB8E50EBB869122" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductOrServiceAxis" xlink:label="loc_us-gaap_ProductOrServiceAxis_840978FD7A92819F1F83E50EBB864EF7" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_978D54DDCBB91AD9CAB8E50EBB869122" xlink:to="loc_us-gaap_ProductOrServiceAxis_840978FD7A92819F1F83E50EBB864EF7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductsAndServicesDomain" xlink:label="loc_us-gaap_ProductsAndServicesDomain_B7238B6E3B1A70D18808E50EBB86897D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ProductOrServiceAxis_840978FD7A92819F1F83E50EBB864EF7" xlink:to="loc_us-gaap_ProductsAndServicesDomain_B7238B6E3B1A70D18808E50EBB86897D" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_CoStarSuiteMember" xlink:label="loc_csgp_CoStarSuiteMember_81F44F10F9BD794AE285E50EBB861462" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ProductsAndServicesDomain_B7238B6E3B1A70D18808E50EBB86897D" xlink:to="loc_csgp_CoStarSuiteMember_81F44F10F9BD794AE285E50EBB861462" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_InformationservicesMember" xlink:label="loc_csgp_InformationservicesMember_060DE122160710F9C123E50EBB862844" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ProductsAndServicesDomain_B7238B6E3B1A70D18808E50EBB86897D" xlink:to="loc_csgp_InformationservicesMember_060DE122160710F9C123E50EBB862844" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_MultifamilyOnlineMarketplaceMember" xlink:label="loc_csgp_MultifamilyOnlineMarketplaceMember_8DDBB77AF89DB65A5BB2E50EBB8CB1F6" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ProductsAndServicesDomain_B7238B6E3B1A70D18808E50EBB86897D" xlink:to="loc_csgp_MultifamilyOnlineMarketplaceMember_8DDBB77AF89DB65A5BB2E50EBB8CB1F6" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_CommercialpropertyandlandMember" xlink:label="loc_csgp_CommercialpropertyandlandMember_9B0304DFC687C163EC00E50EBB8CF9E8" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ProductsAndServicesDomain_B7238B6E3B1A70D18808E50EBB86897D" xlink:to="loc_csgp_CommercialpropertyandlandMember_9B0304DFC687C163EC00E50EBB8CF9E8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems" xlink:label="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_50ECF671D62086441243E50EBB8C3F52" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_978D54DDCBB91AD9CAB8E50EBB869122" xlink:to="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_50ECF671D62086441243E50EBB8C3F52" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_E54A5C9544DCAE6128BFE50EBB8C5875" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_50ECF671D62086441243E50EBB8C3F52" xlink:to="loc_us-gaap_Revenues_E54A5C9544DCAE6128BFE50EBB8C5875" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SegmentReportingTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentReportingAbstract" xlink:label="loc_us-gaap_SegmentReportingAbstract_00B9D4FD9BB062035072DA91C5335A3B" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_A22AFA496148D3B11564DA91C5334C9D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingAbstract_00B9D4FD9BB062035072DA91C5335A3B" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_A22AFA496148D3B11564DA91C5334C9D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock" xlink:label="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock_837868A7960C52D3C367DA91C533FCF7" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingAbstract_00B9D4FD9BB062035072DA91C5335A3B" xlink:to="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock_837868A7960C52D3C367DA91C533FCF7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock" xlink:label="loc_us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock_BEE44B4677425CF2F16BDA91C53300B8" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingAbstract_00B9D4FD9BB062035072DA91C5335A3B" xlink:to="loc_us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock_BEE44B4677425CF2F16BDA91C53300B8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTextBlock" xlink:label="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTextBlock_8114306DAC0011CA9FD4DA91C5332A75" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SegmentReportingAbstract_00B9D4FD9BB062035072DA91C5335A3B" xlink:to="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTextBlock_8114306DAC0011CA9FD4DA91C5332A75" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/StockholdersEquity" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockholdersEquityNoteAbstract" xlink:label="loc_us-gaap_StockholdersEquityNoteAbstract_E82E647FAC237062C9FDDA91C4E78AFE" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:label="loc_us-gaap_StockholdersEquityNoteDisclosureTextBlock_63765499CC8824ABFA82DA91C4E7FBFA" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StockholdersEquityNoteAbstract_E82E647FAC237062C9FDDA91C4E78AFE" xlink:to="loc_us-gaap_StockholdersEquityNoteDisclosureTextBlock_63765499CC8824ABFA82DA91C4E7FBFA" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/StockholdersEquityDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockholdersEquityNoteAbstract" xlink:label="loc_us-gaap_StockholdersEquityNoteAbstract_C9908733B478EC406A2ABAB94348CBF0" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PreferredStockNumberOfSharesParValueAndOtherDisclosuresAbstract" xlink:label="loc_us-gaap_PreferredStockNumberOfSharesParValueAndOtherDisclosuresAbstract_61698EE961747FB0398ABAB94349B106" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StockholdersEquityNoteAbstract_C9908733B478EC406A2ABAB94348CBF0" xlink:to="loc_us-gaap_PreferredStockNumberOfSharesParValueAndOtherDisclosuresAbstract_61698EE961747FB0398ABAB94349B106" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized_DAFEB09A71419EE6D2C4BAB943494C9E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PreferredStockNumberOfSharesParValueAndOtherDisclosuresAbstract_61698EE961747FB0398ABAB94349B106" xlink:to="loc_us-gaap_PreferredStockSharesAuthorized_DAFEB09A71419EE6D2C4BAB943494C9E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PreferredStockParOrStatedValuePerShare" xlink:label="loc_us-gaap_PreferredStockParOrStatedValuePerShare_F4AF40E55C30B4DF1BDABAB94349DE0B" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PreferredStockNumberOfSharesParValueAndOtherDisclosuresAbstract_61698EE961747FB0398ABAB94349B106" xlink:to="loc_us-gaap_PreferredStockParOrStatedValuePerShare_F4AF40E55C30B4DF1BDABAB94349DE0B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommonStockNumberOfSharesParValueAndOtherDisclosuresAbstract" xlink:label="loc_us-gaap_CommonStockNumberOfSharesParValueAndOtherDisclosuresAbstract_6B7419B508B2AF5EADB8BAB94349F3A2" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StockholdersEquityNoteAbstract_C9908733B478EC406A2ABAB94348CBF0" xlink:to="loc_us-gaap_CommonStockNumberOfSharesParValueAndOtherDisclosuresAbstract_6B7419B508B2AF5EADB8BAB94349F3A2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_5762F3DBB61E02FE63C0BAB94349D85B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommonStockNumberOfSharesParValueAndOtherDisclosuresAbstract_6B7419B508B2AF5EADB8BAB94349F3A2" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_5762F3DBB61E02FE63C0BAB94349D85B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_7F1AEB5367544EEE7A9FBAB943499F82" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommonStockNumberOfSharesParValueAndOtherDisclosuresAbstract_6B7419B508B2AF5EADB8BAB94349F3A2" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_7F1AEB5367544EEE7A9FBAB943499F82" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProceedsFromRepurchaseOfEquityAbstract" xlink:label="loc_us-gaap_ProceedsFromRepurchaseOfEquityAbstract_558041553FA109B6FB2FBAB94349F11B" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StockholdersEquityNoteAbstract_C9908733B478EC406A2ABAB94348CBF0" xlink:to="loc_us-gaap_ProceedsFromRepurchaseOfEquityAbstract_558041553FA109B6FB2FBAB94349F11B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_FDCF2693C13D31AE0193BAB943494C40" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ProceedsFromRepurchaseOfEquityAbstract_558041553FA109B6FB2FBAB94349F11B" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_FDCF2693C13D31AE0193BAB943494C40" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharesIssuedPricePerShare" xlink:label="loc_us-gaap_SharesIssuedPricePerShare_7C0E88A8D03215F17147BAB9434A0AE8" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ProceedsFromRepurchaseOfEquityAbstract_558041553FA109B6FB2FBAB94349F11B" xlink:to="loc_us-gaap_SharesIssuedPricePerShare_7C0E88A8D03215F17147BAB9434A0AE8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_0F43B800F58B5F709581BAB9434A0F50" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ProceedsFromRepurchaseOfEquityAbstract_558041553FA109B6FB2FBAB94349F11B" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_0F43B800F58B5F709581BAB9434A0F50" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentsForUnderwritingExpense" xlink:label="loc_us-gaap_PaymentsForUnderwritingExpense_6A55ED6EE4F4F514F347BAB9434AC79F" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ProceedsFromRepurchaseOfEquityAbstract_558041553FA109B6FB2FBAB94349F11B" xlink:to="loc_us-gaap_PaymentsForUnderwritingExpense_6A55ED6EE4F4F514F347BAB9434AC79F" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SubsequentEvents" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventsAbstract" xlink:label="loc_us-gaap_SubsequentEventsAbstract_B53B3A78BB567EE7B395BB66C5459CA9" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventsTextBlock" xlink:label="loc_us-gaap_SubsequentEventsTextBlock_B515599D3E7E6399B904BB670EA11A5E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsequentEventsAbstract_B53B3A78BB567EE7B395BB66C5459CA9" xlink:to="loc_us-gaap_SubsequentEventsTextBlock_B515599D3E7E6399B904BB670EA11A5E" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SubsequentEventsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventsAbstract" xlink:label="loc_us-gaap_SubsequentEventsAbstract_731321F6C04F50B489AFBC3D754ED449" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventTable" xlink:label="loc_us-gaap_SubsequentEventTable_F78673B2939C53DC6749BC3D75C8FB14" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsequentEventsAbstract_731321F6C04F50B489AFBC3D754ED449" xlink:to="loc_us-gaap_SubsequentEventTable_F78673B2939C53DC6749BC3D75C8FB14" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_EE6398808E24BDCE2B56BC3DD137D955" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsequentEventTable_F78673B2939C53DC6749BC3D75C8FB14" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_EE6398808E24BDCE2B56BC3DD137D955" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_EFFC114BCCBE0D29E0A1BC3DD1392E14" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_EE6398808E24BDCE2B56BC3DD137D955" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_EFFC114BCCBE0D29E0A1BC3DD1392E14" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_ForRentDivisionOfDEHoldingsInc.Member" xlink:label="loc_csgp_ForRentDivisionOfDEHoldingsInc.Member_E949231815E959285B69BC3F46A32A88" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_EFFC114BCCBE0D29E0A1BC3DD1392E14" xlink:to="loc_csgp_ForRentDivisionOfDEHoldingsInc.Member_E949231815E959285B69BC3F46A32A88" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_273078C33EDCC60146DEBC3D75C921DC" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsequentEventTable_F78673B2939C53DC6749BC3D75C8FB14" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_273078C33EDCC60146DEBC3D75C921DC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_59E73BE6544EEE034C12BC3D75C9502B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_273078C33EDCC60146DEBC3D75C921DC" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_59E73BE6544EEE034C12BC3D75C9502B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventMember" xlink:label="loc_us-gaap_SubsequentEventMember_34840161418F8DFC8B09BC3DA82EF3F9" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_59E73BE6544EEE034C12BC3D75C9502B" xlink:to="loc_us-gaap_SubsequentEventMember_34840161418F8DFC8B09BC3DA82EF3F9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventLineItems" xlink:label="loc_us-gaap_SubsequentEventLineItems_5C32C96D7293E5E3C24EBC3D75C98A1D" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsequentEventTable_F78673B2939C53DC6749BC3D75C8FB14" xlink:to="loc_us-gaap_SubsequentEventLineItems_5C32C96D7293E5E3C24EBC3D75C98A1D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationConsiderationTransferred1" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_1AB51B93AECE7AAC119DBC4064151ED8" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsequentEventLineItems_5C32C96D7293E5E3C24EBC3D75C98A1D" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_1AB51B93AECE7AAC119DBC4064151ED8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentsToAcquireBusinessesGross" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesGross_A96B96D478094E95547ABC43EA039971" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsequentEventLineItems_5C32C96D7293E5E3C24EBC3D75C98A1D" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesGross_A96B96D478094E95547ABC43EA039971" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable_B44B39BD05E6C223A3DEBC4252EBD282" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsequentEventLineItems_5C32C96D7293E5E3C24EBC3D75C98A1D" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable_B44B39BD05E6C223A3DEBC4252EBD282" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SummaryOfSignificantAccountingPolicies" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract_F1759A38411B70A255E3DA91C4501DFE" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureAndSignificantAccountingPoliciesTextBlock" xlink:label="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureAndSignificantAccountingPoliciesTextBlock_74888577164731E56B50DA91C450304E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_F1759A38411B70A255E3DA91C4501DFE" xlink:to="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureAndSignificantAccountingPoliciesTextBlock_74888577164731E56B50DA91C450304E" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesDetailsCashAndCashEquivalentsAndConcentrationOfCreditRisk" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashAndCashEquivalentsAbstract" xlink:label="loc_us-gaap_CashAndCashEquivalentsAbstract_4D1FC48ECB98B710794BDA91C50974B4" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConcentrationRiskCustomer" xlink:label="loc_us-gaap_ConcentrationRiskCustomer_C2B53980AC394E30CE42DA91C509B259" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CashAndCashEquivalentsAbstract_4D1FC48ECB98B710794BDA91C50974B4" xlink:to="loc_us-gaap_ConcentrationRiskCustomer_C2B53980AC394E30CE42DA91C509B259" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdditionalCashAndCashEquivalentRelatedText" xlink:label="loc_us-gaap_AdditionalCashAndCashEquivalentRelatedText_843CB071EC0D7AB70CE6DA91C509B9FB" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CashAndCashEquivalentsAbstract_4D1FC48ECB98B710794BDA91C50974B4" xlink:to="loc_us-gaap_AdditionalCashAndCashEquivalentRelatedText_843CB071EC0D7AB70CE6DA91C509B9FB" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesDetailsDebtIssuanceCostsAndRecentAccountingPronouncements" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureAbstract" xlink:label="loc_us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureAbstract_8E08E9931E5E2C64D028BAB944817411" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredFinanceCostsNet" xlink:label="loc_us-gaap_DeferredFinanceCostsNet_F3FD705725F8E15E1674BAB944816865" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureAbstract_8E08E9931E5E2C64D028BAB944817411" xlink:to="loc_us-gaap_DeferredFinanceCostsNet_F3FD705725F8E15E1674BAB944816865" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="loc_us-gaap_AmortizationOfFinancingCosts_435C2FFFE6C93ED6A5F8BAB944827CC9" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureAbstract_8E08E9931E5E2C64D028BAB944817411" xlink:to="loc_us-gaap_AmortizationOfFinancingCosts_435C2FFFE6C93ED6A5F8BAB944827CC9" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesDetailsForeignCurrencyTranslationAndAccumulatedOtherComprehensiveLoss" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract_F232B42BD4CBDCC600CEBAB944F32748" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTaxAbstract" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTaxAbstract_A376EDD86D0A793FEF5EBAB944F3DB00" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_F232B42BD4CBDCC600CEBAB944F32748" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTaxAbstract_A376EDD86D0A793FEF5EBAB944F3DB00" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ForeignCurrencyTransactionGainLossBeforeTax" xlink:label="loc_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_6CE58BCE461089D1E4D2BAB944F374BC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTaxAbstract_A376EDD86D0A793FEF5EBAB944F3DB00" xlink:to="loc_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_6CE58BCE461089D1E4D2BAB944F374BC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax_7CB238B2D17A7A6BDDA8BAB944F36291" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTaxAbstract_A376EDD86D0A793FEF5EBAB944F3DB00" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax_7CB238B2D17A7A6BDDA8BAB944F36291" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_F3FA437A1093E33CAF6EBAB944F34EAD" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTaxAbstract_A376EDD86D0A793FEF5EBAB944F3DB00" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_F3FA437A1093E33CAF6EBAB944F34EAD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_5E8CCA8A2C008B284A02BAB944F3BB81" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTaxAbstract_A376EDD86D0A793FEF5EBAB944F3DB00" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_5E8CCA8A2C008B284A02BAB944F3BB81" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_4B4B9426329E1EB2729DBAB944F333DE" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTaxAbstract_A376EDD86D0A793FEF5EBAB944F3DB00" xlink:to="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_4B4B9426329E1EB2729DBAB944F333DE" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesDetailsGoodwillAndIntangibleAssets" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract" xlink:label="loc_us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract_536F8850A8F090F5B41FDA91C50E4219" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_D60D219990C591A4CB26DA91C50E501F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract_536F8850A8F090F5B41FDA91C50E4219" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_D60D219990C591A4CB26DA91C50E501F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_9BE5F67892A8BDAC4CDDDA91C50ED279" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_D60D219990C591A4CB26DA91C50E501F" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_9BE5F67892A8BDAC4CDDDA91C50ED279" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_49DB817D2103AE458812DA91C50E5769" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_9BE5F67892A8BDAC4CDDDA91C50ED279" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_49DB817D2103AE458812DA91C50E5769" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DatabasesMember" xlink:label="loc_us-gaap_DatabasesMember_D1622DB333EECCEC6D5EDA91C50E16AF" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_49DB817D2103AE458812DA91C50E5769" xlink:to="loc_us-gaap_DatabasesMember_D1622DB333EECCEC6D5EDA91C50E16AF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TradeNamesMember" xlink:label="loc_us-gaap_TradeNamesMember_76415D30C0425E8A28CEDA91C50F47C2" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_49DB817D2103AE458812DA91C50E5769" xlink:to="loc_us-gaap_TradeNamesMember_76415D30C0425E8A28CEDA91C50F47C2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CustomerContractsMember" xlink:label="loc_us-gaap_CustomerContractsMember_32DB84F6E55F4D36708BDA91C50F7B41" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_49DB817D2103AE458812DA91C50E5769" xlink:to="loc_us-gaap_CustomerContractsMember_32DB84F6E55F4D36708BDA91C50F7B41" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_BuildingPhotographyMember" xlink:label="loc_csgp_BuildingPhotographyMember_8D0F4FD853365C2DF439DA91C50F75E8" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_49DB817D2103AE458812DA91C50E5769" xlink:to="loc_csgp_BuildingPhotographyMember_8D0F4FD853365C2DF439DA91C50F75E8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_122FC1ED6D34984EC929DA91C50F6A15" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_D60D219990C591A4CB26DA91C50E501F" xlink:to="loc_us-gaap_RangeAxis_122FC1ED6D34984EC929DA91C50F6A15" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_0B17232D666180C45565DA91C50F8FD3" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RangeAxis_122FC1ED6D34984EC929DA91C50F6A15" xlink:to="loc_us-gaap_RangeMember_0B17232D666180C45565DA91C50F8FD3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_61F7C29DB1DF3A1B7EE3DA91C50F9362" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RangeMember_0B17232D666180C45565DA91C50F8FD3" xlink:to="loc_us-gaap_MinimumMember_61F7C29DB1DF3A1B7EE3DA91C50F9362" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_F0603589BD1C220B8BB3DA91C50F0124" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RangeMember_0B17232D666180C45565DA91C50F8FD3" xlink:to="loc_us-gaap_MaximumMember_F0603589BD1C220B8BB3DA91C50F0124" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_D14C6BE375B233EDD0D2DA91C50FA1E7" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_D60D219990C591A4CB26DA91C50E501F" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_D14C6BE375B233EDD0D2DA91C50FA1E7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_5EA211392F13F30A9BADDA91C50F596B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_D14C6BE375B233EDD0D2DA91C50FA1E7" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_5EA211392F13F30A9BADDA91C50F596B" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesDetailsPropertyAndEquipment" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAbstract" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAbstract_4C4FA6CC0C8331E980E2DA91C52EBA0D" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_33A5E583424579930C35DA91C52E41F5" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAbstract_4C4FA6CC0C8331E980E2DA91C52EBA0D" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_33A5E583424579930C35DA91C52E41F5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_86E9F241FB6798DDBED7DA91C52E3BDD" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_33A5E583424579930C35DA91C52E41F5" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_86E9F241FB6798DDBED7DA91C52E3BDD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_436C954B3066DF011EA5DA91C52E8E60" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_86E9F241FB6798DDBED7DA91C52E3BDD" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_436C954B3066DF011EA5DA91C52E8E60" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LeaseholdImprovementsMember" xlink:label="loc_us-gaap_LeaseholdImprovementsMember_AE081503519135DDFF6CDA91C52EFF2F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_436C954B3066DF011EA5DA91C52E8E60" xlink:to="loc_us-gaap_LeaseholdImprovementsMember_AE081503519135DDFF6CDA91C52EFF2F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FurnitureAndFixturesMember" xlink:label="loc_us-gaap_FurnitureAndFixturesMember_EACDCD87B4AE1122C341DA91C52FB5F9" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_436C954B3066DF011EA5DA91C52E8E60" xlink:to="loc_us-gaap_FurnitureAndFixturesMember_EACDCD87B4AE1122C341DA91C52FB5F9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VehiclesMember" xlink:label="loc_us-gaap_VehiclesMember_E334B5A1E59C3ED5DD32DA91C52FDA45" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_436C954B3066DF011EA5DA91C52E8E60" xlink:to="loc_us-gaap_VehiclesMember_E334B5A1E59C3ED5DD32DA91C52FDA45" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ComputerEquipmentMember" xlink:label="loc_us-gaap_ComputerEquipmentMember_057DB3836D79B5E7B5CDDA91C52F6ED8" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_436C954B3066DF011EA5DA91C52E8E60" xlink:to="loc_us-gaap_ComputerEquipmentMember_057DB3836D79B5E7B5CDDA91C52F6ED8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_62F1C82E8291AE161FBFDA91C52FE053" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_33A5E583424579930C35DA91C52E41F5" xlink:to="loc_us-gaap_RangeAxis_62F1C82E8291AE161FBFDA91C52FE053" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_48A50C7922C97EF252CBDA91C52FC259" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RangeAxis_62F1C82E8291AE161FBFDA91C52FE053" xlink:to="loc_us-gaap_RangeMember_48A50C7922C97EF252CBDA91C52FC259" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_D44FDA8AEEB094F587B4DA91C52F0542" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RangeMember_48A50C7922C97EF252CBDA91C52FC259" xlink:to="loc_us-gaap_MinimumMember_D44FDA8AEEB094F587B4DA91C52F0542" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_E317DB4878E7D1342B0BDA91C52FF52F" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RangeMember_48A50C7922C97EF252CBDA91C52FC259" xlink:to="loc_us-gaap_MaximumMember_E317DB4878E7D1342B0BDA91C52FF52F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentLineItems" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ED2F3A02922A824688B0DA91C52FDFC3" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_33A5E583424579930C35DA91C52E41F5" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ED2F3A02922A824688B0DA91C52FDFC3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentEstimatedUsefulLives" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentEstimatedUsefulLives_B24CE81B6F027D4A5E21DA91C52FA0CB" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ED2F3A02922A824688B0DA91C52FDFC3" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentEstimatedUsefulLives_B24CE81B6F027D4A5E21DA91C52FA0CB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_FD51A8E6EF7288055B58DA91C52FCF6A" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_ED2F3A02922A824688B0DA91C52FDFC3" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_FD51A8E6EF7288055B58DA91C52FCF6A" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesDetailsRevenueRecognitionAndAdvertisingCosts" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract_EC2FA8733137DA0499CEDA91C4A28DA1" xlink:type="locator" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_SubscriptionBasedLicensingAgreementMinimumTermYears" xlink:label="loc_csgp_SubscriptionBasedLicensingAgreementMinimumTermYears_71651D77A2014E560722DA91C4A21DEC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_EC2FA8733137DA0499CEDA91C4A28DA1" xlink:to="loc_csgp_SubscriptionBasedLicensingAgreementMinimumTermYears_71651D77A2014E560722DA91C4A21DEC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdvertisingExpense" xlink:label="loc_us-gaap_AdvertisingExpense_C354EE8376485CE93F32DA91C4A205F6" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_EC2FA8733137DA0499CEDA91C4A28DA1" xlink:to="loc_us-gaap_AdvertisingExpense_C354EE8376485CE93F32DA91C4A205F6" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesDetailsStockBasedCompensation" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract_6836E1C2681D8EC42752BAB944EFA787" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_7DC33860A6F67210C560BAB944EFBDF5" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_6836E1C2681D8EC42752BAB944EFA787" xlink:to="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_7DC33860A6F67210C560BAB944EFBDF5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaap_AwardTypeAxis_FD821B7ECF8F938FE043BAB944EFF29A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_7DC33860A6F67210C560BAB944EFBDF5" xlink:to="loc_us-gaap_AwardTypeAxis_FD821B7ECF8F938FE043BAB944EFF29A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_55C5E5E969B2C3CA0596BAB944EFF306" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AwardTypeAxis_FD821B7ECF8F938FE043BAB944EFF29A" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_55C5E5E969B2C3CA0596BAB944EFF306" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_PerformancebasedRSAswithMarketConditionMember" xlink:label="loc_csgp_PerformancebasedRSAswithMarketConditionMember_6E7EF22995DA32F64093BAB944EF0163" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_55C5E5E969B2C3CA0596BAB944EFF306" xlink:to="loc_csgp_PerformancebasedRSAswithMarketConditionMember_6E7EF22995DA32F64093BAB944EF0163" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_15395A28FD52A6A48E39BAB944EFDF07" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_7DC33860A6F67210C560BAB944EFBDF5" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_15395A28FD52A6A48E39BAB944EFDF07" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_930D7E973585B6F3BEB6BAB944EFF396" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_15395A28FD52A6A48E39BAB944EFDF07" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_930D7E973585B6F3BEB6BAB944EFF396" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CostOfSalesMember" xlink:label="loc_us-gaap_CostOfSalesMember_14319D7C691660A276EFBAB944EF6194" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_930D7E973585B6F3BEB6BAB944EFF396" xlink:to="loc_us-gaap_CostOfSalesMember_14319D7C691660A276EFBAB944EF6194" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SellingAndMarketingExpenseMember" xlink:label="loc_us-gaap_SellingAndMarketingExpenseMember_EFDDB789BEA2A69BD339BAB944EF8B94" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_930D7E973585B6F3BEB6BAB944EFF396" xlink:to="loc_us-gaap_SellingAndMarketingExpenseMember_EFDDB789BEA2A69BD339BAB944EF8B94" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SoftwareDevelopmentMember" xlink:label="loc_us-gaap_SoftwareDevelopmentMember_1EFDD921C71FD9862E1FBAB944F08CD6" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_930D7E973585B6F3BEB6BAB944EFF396" xlink:to="loc_us-gaap_SoftwareDevelopmentMember_1EFDD921C71FD9862E1FBAB944F08CD6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GeneralAndAdministrativeExpenseMember" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpenseMember_F980A49AA22D0F298D0ABAB944F07C02" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_930D7E973585B6F3BEB6BAB944EFF396" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpenseMember_F980A49AA22D0F298D0ABAB944F07C02" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_6FCF017856C820CA4F26BAB944F0B9C3" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_7DC33860A6F67210C560BAB944EFBDF5" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_6FCF017856C820CA4F26BAB944F0B9C3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:label="loc_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_D1C345C19080B8EFEBAEBAB944F0D1E3" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_6FCF017856C820CA4F26BAB944F0B9C3" xlink:to="loc_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_D1C345C19080B8EFEBAEBAB944F0D1E3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AllocatedShareBasedCompensationExpense" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_8C74F6C27303C42BA5F6BAB944F0535A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_D1C345C19080B8EFEBAEBAB944F0D1E3" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_8C74F6C27303C42BA5F6BAB944F0535A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_A4C2073E95AADDC5E9CBBAB944F04628" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_D1C345C19080B8EFEBAEBAB944F0D1E3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_A4C2073E95AADDC5E9CBBAB944F04628" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_0CEF71765F297910531EBAB944F02DAA" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_D1C345C19080B8EFEBAEBAB944F0D1E3" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_0CEF71765F297910531EBAB944F02DAA" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_ProceedsFromExerciseOfStockOptionsAndEspp" xlink:label="loc_csgp_ProceedsFromExerciseOfStockOptionsAndEspp_E6A6963ED7E66FA196E8BAB944F068EA" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_D1C345C19080B8EFEBAEBAB944F0D1E3" xlink:to="loc_csgp_ProceedsFromExerciseOfStockOptionsAndEspp_E6A6963ED7E66FA196E8BAB944F068EA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxExpenseFromStockOptionsExercised" xlink:label="loc_us-gaap_DeferredTaxExpenseFromStockOptionsExercised_7C885B4FE4AF516B6CA8BAB944F09F06" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_D1C345C19080B8EFEBAEBAB944F0D1E3" xlink:to="loc_us-gaap_DeferredTaxExpenseFromStockOptionsExercised_7C885B4FE4AF516B6CA8BAB944F09F06" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesPolicies" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConsolidationPolicyTextBlock" xlink:label="loc_us-gaap_ConsolidationPolicyTextBlock_F9A9B227FE31AC723047DA91C51C039A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_ConsolidationPolicyTextBlock_F9A9B227FE31AC723047DA91C51C039A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UseOfEstimates" xlink:label="loc_us-gaap_UseOfEstimates_9A7C49C25E11BD58783FDA91C51CDC33" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_UseOfEstimates_9A7C49C25E11BD58783FDA91C51CDC33" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueRecognitionPolicyTextBlock" xlink:label="loc_us-gaap_RevenueRecognitionPolicyTextBlock_941EC1C8BDC52DC41C78DA91C51CF771" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_RevenueRecognitionPolicyTextBlock_941EC1C8BDC52DC41C78DA91C51CF771" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CostOfSalesPolicyTextBlock" xlink:label="loc_us-gaap_CostOfSalesPolicyTextBlock_CE676275539A6D177EC5DA91C51CE56D" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_CostOfSalesPolicyTextBlock_CE676275539A6D177EC5DA91C51CE56D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock" xlink:label="loc_us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock_0562D6E7A5B08B1D529DDA91C51C4A46" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock_0562D6E7A5B08B1D529DDA91C51C4A46" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdvertisingCostsPolicyTextBlock" xlink:label="loc_us-gaap_AdvertisingCostsPolicyTextBlock_EBD32ECF8BAB3668F5EBDA91C51C8A1A" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_AdvertisingCostsPolicyTextBlock_EBD32ECF8BAB3668F5EBDA91C51C8A1A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxPolicyTextBlock" xlink:label="loc_us-gaap_IncomeTaxPolicyTextBlock_5DEF2EBE060F53FE2884DA91C51C7DC1" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_IncomeTaxPolicyTextBlock_5DEF2EBE060F53FE2884DA91C51C7DC1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerSharePolicyTextBlock" xlink:label="loc_us-gaap_EarningsPerSharePolicyTextBlock_9185FB366AC72C47A625DA91C51DB258" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_EarningsPerSharePolicyTextBlock_9185FB366AC72C47A625DA91C51DB258" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy" xlink:label="loc_us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_8DA7D6D3A49A7411B111DA91C51D9C0F" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_8DA7D6D3A49A7411B111DA91C51D9C0F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:label="loc_us-gaap_CashAndCashEquivalentsPolicyTextBlock_13D737151A099DAA9CF7DA91C51D1675" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_CashAndCashEquivalentsPolicyTextBlock_13D737151A099DAA9CF7DA91C51D1675" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InvestmentPolicyTextBlock" xlink:label="loc_us-gaap_InvestmentPolicyTextBlock_0DF9E6BAEB02DCF1CA30DA91C51D0F05" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_InvestmentPolicyTextBlock_0DF9E6BAEB02DCF1CA30DA91C51D0F05" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConcentrationRiskCreditRisk" xlink:label="loc_us-gaap_ConcentrationRiskCreditRisk_A45FF5EA8157C14265EEDA91C51D206C" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_ConcentrationRiskCreditRisk_A45FF5EA8157C14265EEDA91C51D206C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TradeAndOtherAccountsReceivablePolicy" xlink:label="loc_us-gaap_TradeAndOtherAccountsReceivablePolicy_9FADD914A8068391986EDA91C51DB893" xlink:type="locator" />
    <link:presentationArc order="13" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_TradeAndOtherAccountsReceivablePolicy_9FADD914A8068391986EDA91C51DB893" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentPolicyTextBlock" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_F17AF5F87333895BCC65DA91C51DD479" xlink:type="locator" />
    <link:presentationArc order="14" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_F17AF5F87333895BCC65DA91C51DD479" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock" xlink:label="loc_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_C9DE892324D7FC8369ACDA91C51D80AB" xlink:type="locator" />
    <link:presentationArc order="15" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_C9DE892324D7FC8369ACDA91C51D80AB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock" xlink:label="loc_us-gaap_ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock_5E2B3F97E4106C477A6EDA91C51D6908" xlink:type="locator" />
    <link:presentationArc order="16" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock_5E2B3F97E4106C477A6EDA91C51D6908" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtPolicyTextBlock" xlink:label="loc_us-gaap_DebtPolicyTextBlock_CBCB1EE6B05A8B1600D1DA91C51D23AF" xlink:type="locator" />
    <link:presentationArc order="17" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_DebtPolicyTextBlock_CBCB1EE6B05A8B1600D1DA91C51D23AF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationsPolicy" xlink:label="loc_us-gaap_BusinessCombinationsPolicy_A9EDF5D39E1D6A1EC469DA91C51D27F0" xlink:type="locator" />
    <link:presentationArc order="18" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_BusinessCombinationsPolicy_A9EDF5D39E1D6A1EC469DA91C51D27F0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:label="loc_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_2BAC849265CB9D3DA019DA91C51D6AE6" xlink:type="locator" />
    <link:presentationArc order="19" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_3CF1598799F1F6539877DA91C51CE799" xlink:to="loc_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_2BAC849265CB9D3DA019DA91C51D6AE6" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesRecentAccountingPronouncementsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract_4168E8648697F282CCE6BC17C95F8E35" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_D2821172C0B8AAF0481BBC17C95FA849" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_4168E8648697F282CCE6BC17C95F8E35" xlink:to="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_D2821172C0B8AAF0481BBC17C95FA849" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_32085E11B88C179FA11FBC321E26DE4A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_D2821172C0B8AAF0481BBC17C95FA849" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_32085E11B88C179FA11FBC321E26DE4A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_2F951FCE8907E3E7696FBC321E2A7DE7" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_32085E11B88C179FA11FBC321E26DE4A" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_2F951FCE8907E3E7696FBC321E2A7DE7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventMember" xlink:label="loc_us-gaap_SubsequentEventMember_9C56A4FECA24069FD96DBC323B6265E4" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_2F951FCE8907E3E7696FBC321E2A7DE7" xlink:to="loc_us-gaap_SubsequentEventMember_9C56A4FECA24069FD96DBC323B6265E4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_8D654CDF1A869176466BBC2C9F0DA061" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_D2821172C0B8AAF0481BBC17C95FA849" xlink:to="loc_us-gaap_RangeAxis_8D654CDF1A869176466BBC2C9F0DA061" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_1142E4357436F95190BABC2C9F210343" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RangeAxis_8D654CDF1A869176466BBC2C9F0DA061" xlink:to="loc_us-gaap_RangeMember_1142E4357436F95190BABC2C9F210343" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_0EA95A31C700C26F061ABC2CD2CED279" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RangeMember_1142E4357436F95190BABC2C9F210343" xlink:to="loc_us-gaap_MinimumMember_0EA95A31C700C26F061ABC2CD2CED279" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_758DCB14B0FA6E0B5F83BC2CF722B661" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RangeMember_1142E4357436F95190BABC2C9F210343" xlink:to="loc_us-gaap_MaximumMember_758DCB14B0FA6E0B5F83BC2CF722B661" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_F5DA11506B2FDF17A035BC17C95F734F" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_D2821172C0B8AAF0481BBC17C95FA849" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_F5DA11506B2FDF17A035BC17C95F734F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_540377B021994BFE5158BC17C95FFBC1" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_F5DA11506B2FDF17A035BC17C95F734F" xlink:to="loc_us-gaap_EquityComponentDomain_540377B021994BFE5158BC17C95FFBC1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaap_RetainedEarningsMember_AD9E55BB66B1ECF59C1BBC17C960564C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityComponentDomain_540377B021994BFE5158BC17C95FFBC1" xlink:to="loc_us-gaap_RetainedEarningsMember_AD9E55BB66B1ECF59C1BBC17C960564C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" xlink:label="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_65FE6E9D20AC9F9066B2BC17C96099E3" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_D2821172C0B8AAF0481BBC17C95FA849" xlink:to="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_65FE6E9D20AC9F9066B2BC17C96099E3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_97749348F434D51D7E3CBC17C9600736" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_65FE6E9D20AC9F9066B2BC17C96099E3" xlink:to="loc_us-gaap_TypeOfAdoptionMember_97749348F434D51D7E3CBC17C9600736" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_AccountingStandardsUpdate201609ExcessTaxBenefitComponentMember" xlink:label="loc_csgp_AccountingStandardsUpdate201609ExcessTaxBenefitComponentMember_B1C31F53F09CB7283714BC17C9600C3A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_TypeOfAdoptionMember_97749348F434D51D7E3CBC17C9600736" xlink:to="loc_csgp_AccountingStandardsUpdate201609ExcessTaxBenefitComponentMember_B1C31F53F09CB7283714BC17C9600C3A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountingStandardsUpdate201409Member" xlink:label="loc_us-gaap_AccountingStandardsUpdate201409Member_EC25C5BE5DABC567EC7FBC26B34F8C10" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_TypeOfAdoptionMember_97749348F434D51D7E3CBC17C9600736" xlink:to="loc_us-gaap_AccountingStandardsUpdate201409Member_EC25C5BE5DABC567EC7FBC26B34F8C10" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_07FFC19EE5E161E34555BC17C96157B5" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_D2821172C0B8AAF0481BBC17C95FA849" xlink:to="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_07FFC19EE5E161E34555BC17C96157B5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption" xlink:label="loc_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_8F4D7DF6510F06B253E6BC17C9612168" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_07FFC19EE5E161E34555BC17C96157B5" xlink:to="loc_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_8F4D7DF6510F06B253E6BC17C9612168" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredIncomeTaxAssetsNet" xlink:label="loc_us-gaap_DeferredIncomeTaxAssetsNet_8E07B38EF74AB8944672BC244E9A16AB" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_07FFC19EE5E161E34555BC17C96157B5" xlink:to="loc_us-gaap_DeferredIncomeTaxAssetsNet_8E07B38EF74AB8944672BC244E9A16AB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ExcessTaxBenefitFromShareBasedCompensationOperatingActivities" xlink:label="loc_us-gaap_ExcessTaxBenefitFromShareBasedCompensationOperatingActivities_32B0A7C7A4FEB0D1C700BC17C961AE29" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_07FFC19EE5E161E34555BC17C96157B5" xlink:to="loc_us-gaap_ExcessTaxBenefitFromShareBasedCompensationOperatingActivities_32B0A7C7A4FEB0D1C700BC17C961AE29" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredSalesCommission" xlink:label="loc_us-gaap_DeferredSalesCommission_1DD54CC690C48F4644CCBC319ACBD1B2" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_07FFC19EE5E161E34555BC17C96157B5" xlink:to="loc_us-gaap_DeferredSalesCommission_1DD54CC690C48F4644CCBC319ACBD1B2" xlink:type="arc" />
    <link:loc xlink:href="csgp-20171231.xsd#csgp_DeferredSalesCommissionAmortizationPeriod" xlink:label="loc_csgp_DeferredSalesCommissionAmortizationPeriod_836DF7ABD85A8E958CE0BC341E21A854" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_07FFC19EE5E161E34555BC17C96157B5" xlink:to="loc_csgp_DeferredSalesCommissionAmortizationPeriod_836DF7ABD85A8E958CE0BC341E21A854" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://www.costar.com/role/SummaryOfSignificantAccountingPoliciesTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract_AA32456646CBB8AA76D4DA91C40BBD39" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock_E34E882D0AE1E915C521DA91C40B022A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_AA32456646CBB8AA76D4DA91C40BBD39" xlink:to="loc_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock_E34E882D0AE1E915C521DA91C40B022A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_EFFD1557B0B63D7A61F1DA91C40B1498" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_AA32456646CBB8AA76D4DA91C40BBD39" xlink:to="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_EFFD1557B0B63D7A61F1DA91C40B1498" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTextBlock" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTextBlock_675CF0F8D40E55884B05DA91C40BB128" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_AA32456646CBB8AA76D4DA91C40BBD39" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTextBlock_675CF0F8D40E55884B05DA91C40BB128" xlink:type="arc" />
  </link:presentationLink>
</link:linkbase>
