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  <xs:element id="cmcsa_ContributionsFromAndDistributionsToNoncontrollingInterestsAttributableToTemporaryEquity" abstract="false" name="ContributionsFromAndDistributionsToNoncontrollingInterestsAttributableToTemporaryEquity" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_ContributionsFromAndDistributionsToNoncontrollingInterests" abstract="false" name="ContributionsFromAndDistributionsToNoncontrollingInterests" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_ScheduleOfOtherBalanceSheetAccountsRelatedToRecognitionOfRevenueTableTextBlock" abstract="false" name="ScheduleOfOtherBalanceSheetAccountsRelatedToRecognitionOfRevenueTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="cmcsa_ScheduleOfProgrammingAndProductionCostTableTextBlock" abstract="false" name="ScheduleOfProgrammingAndProductionCostTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="cmcsa_ScheduleOfCapitalizedFilmAndTelevisionCostsTableTextBlock" abstract="false" name="ScheduleOfCapitalizedFilmAndTelevisionCostsTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="cmcsa_ScheduleOfEstimatedFutureAmortizationExpenseForCapitalizedFilmAndTelevisionCostTableTextBlock" abstract="false" name="ScheduleOfEstimatedFutureAmortizationExpenseForCapitalizedFilmAndTelevisionCostTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="cmcsa_ScheduleOfAccruedParticipationLiabilitiesDueInNextOperatingCycleTableTextBlock" abstract="false" name="ScheduleOfAccruedParticipationLiabilitiesDueInNextOperatingCycleTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="cmcsa_ComponentsOfInvestmentAndOtherIncomeLossNetTableTextBlock" abstract="false" name="ComponentsOfInvestmentAndOtherIncomeLossNetTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="cmcsa_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsTableTextBlock" abstract="false" name="ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="cmcsa_DeferredCompensationPlansTableTextBlock" abstract="false" name="DeferredCompensationPlansTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="cmcsa_StockOptionFairValueAndSignificantAssumptionsTableTextBlock" abstract="false" name="StockOptionFairValueAndSignificantAssumptionsTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="cmcsa_ScheduleOfCashCashEquivalentsAndRestrictedCashTableTextBlock" abstract="false" name="ScheduleOfCashCashEquivalentsAndRestrictedCashTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="cmcsa_ScheduleOfCurrentAndNoncurrentOperatingLeaseAssetsAndLiabilitiesTableTextBlock" abstract="false" name="ScheduleOfCurrentAndNoncurrentOperatingLeaseAssetsAndLiabilitiesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="cmcsa_ResidentialConnectivityAndPlatformsSegmentMember" abstract="true" name="ResidentialConnectivityAndPlatformsSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_BusinessServicesConnectivitySegmentMember" abstract="true" name="BusinessServicesConnectivitySegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_MediaSegmentMember" abstract="true" name="MediaSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_StudiosSegmentMember" abstract="true" name="StudiosSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_ThemeParksSegmentMember" abstract="true" name="ThemeParksSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_ExternalCustomersMember" abstract="true" name="ExternalCustomersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_IntersegmentCustomersMember" abstract="true" name="IntersegmentCustomersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_CorporateTypeAxis" abstract="true" name="CorporateTypeAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="cmcsa_CorporateTypeDomain" abstract="true" name="CorporateTypeDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_MediaStudiosThemeParksSegmentsHeadquartersAndOtherMember" abstract="true" name="MediaStudiosThemeParksSegmentsHeadquartersAndOtherMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_CorporateAndOtherTypeMember" abstract="true" name="CorporateAndOtherTypeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_AdjustedEBITDA" abstract="false" name="AdjustedEBITDA" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_DomesticBroadbandMember" abstract="true" name="DomesticBroadbandMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_DomesticWirelessMember" abstract="true" name="DomesticWirelessMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_InternationalConnectivityMember" abstract="true" name="InternationalConnectivityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_ResidentialConnectivityMember" abstract="true" name="ResidentialConnectivityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_VideoMember" abstract="true" name="VideoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_OtherMember" abstract="true" name="OtherMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_DomesticAdvertisingMember" abstract="true" name="DomesticAdvertisingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_DomesticDistributionMember" abstract="true" name="DomesticDistributionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_InternationalNetworksMember" abstract="true" name="InternationalNetworksMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_ContentLicensingMember" abstract="true" name="ContentLicensingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_TheatricalMember" abstract="true" name="TheatricalMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_OtherGeographicLocationsMember" abstract="true" name="OtherGeographicLocationsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_MediaSegmentsMember" abstract="true" name="MediaSegmentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_CertainInternationalCustomersUnderContractMember" abstract="true" name="CertainInternationalCustomersUnderContractMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_DistributionMember" abstract="true" name="DistributionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_RevenuePerformanceObligationDescriptionOfTimingTermOfContract" abstract="false" name="RevenuePerformanceObligationDescriptionOfTimingTermOfContract" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="cmcsa_BacklogAsAPercentOfAnnualSegmentRevenuePercent" abstract="false" name="BacklogAsAPercentOfAnnualSegmentRevenuePercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="cmcsa_RevenuePerformanceObligationDescriptionOfTimingTermOfSalesCommission" abstract="false" name="RevenuePerformanceObligationDescriptionOfTimingTermOfSalesCommission" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="cmcsa_RevenuePerformanceObligationDescriptionOfTimingEquipmentInstallmentPlanPaymentTerm" abstract="false" name="RevenuePerformanceObligationDescriptionOfTimingEquipmentInstallmentPlanPaymentTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="cmcsa_RevenuePerformanceObligationDescriptionOfPaymentTermsPeriod" abstract="false" name="RevenuePerformanceObligationDescriptionOfPaymentTermsPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="cmcsa_AccountsReceivableAllowanceForCreditLossWriteOffsNetOfRecoveriesAndOther" abstract="false" name="AccountsReceivableAllowanceForCreditLossWriteOffsNetOfRecoveriesAndOther" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_FinanceReceivableProgramAxis" abstract="true" name="FinanceReceivableProgramAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="cmcsa_FinanceReceivableProgramDomain" abstract="true" name="FinanceReceivableProgramDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_EquipmentInstallmentPlanMember" abstract="true" name="EquipmentInstallmentPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_VideoDistributionProgrammingExpense" abstract="false" name="VideoDistributionProgrammingExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_FilmAndTelevisionContentAbstract" abstract="true" name="FilmAndTelevisionContentAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cmcsa_FilmMonetizedOnItsOwnAmortizationExpenseIncludingParticipationsAndResiduals" abstract="false" name="FilmMonetizedOnItsOwnAmortizationExpenseIncludingParticipationsAndResiduals" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EntertainmentLicenseAgreementForProgramMaterialIncludingSportsRightsAdvancesAmortizationExpense" abstract="false" name="EntertainmentLicenseAgreementForProgramMaterialIncludingSportsRightsAdvancesAmortizationExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_OtherProgrammingAndProductionExpense" abstract="false" name="OtherProgrammingAndProductionExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_FilmMonetizedOnItsOwnCapitalizedCostInProductionAndInDevelopment" abstract="false" name="FilmMonetizedOnItsOwnCapitalizedCostInProductionAndInDevelopment" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EntertainmentLicenseAgreementForProgramMaterialIncludingSportsRightsAdvancesCapitalizedCost" abstract="false" name="EntertainmentLicenseAgreementForProgramMaterialIncludingSportsRightsAdvancesCapitalizedCost" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_FilmMonetizedOnItsOwnCapitalizedCostAndEntertainmentLicenseAgreementForProgramMaterialIncludingSportsRightsAdvances" abstract="false" name="FilmMonetizedOnItsOwnCapitalizedCostAndEntertainmentLicenseAgreementForProgramMaterialIncludingSportsRightsAdvances" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_ProductionTaxIncentivesFilmAndTelevisionOffsetMember" abstract="true" name="ProductionTaxIncentivesFilmAndTelevisionOffsetMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_ProductionTaxIncentivesProgrammingAndProductionCostsOffsetMember" abstract="true" name="ProductionTaxIncentivesProgrammingAndProductionCostsOffsetMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_ProductionTaxIncentivesReceivableMember" abstract="true" name="ProductionTaxIncentivesReceivableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_BroadcastersLicenseAgreementCommitmentsAmount" abstract="false" name="BroadcastersLicenseAgreementCommitmentsAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EntertainmentLicenseAgreementForProgramMaterialIncludingSportsRightsAdvancesExpectedAmortizationYearOne" abstract="false" name="EntertainmentLicenseAgreementForProgramMaterialIncludingSportsRightsAdvancesExpectedAmortizationYearOne" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EntertainmentLicenseAgreementForProgramMaterialIncludingSportsRightsAdvancesExpectedAmortizationYearTwo" abstract="false" name="EntertainmentLicenseAgreementForProgramMaterialIncludingSportsRightsAdvancesExpectedAmortizationYearTwo" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EntertainmentLicenseAgreementForProgramMaterialIncludingSportsRightsAdvancesExpectedAmortizationYearThree" abstract="false" name="EntertainmentLicenseAgreementForProgramMaterialIncludingSportsRightsAdvancesExpectedAmortizationYearThree" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EffectiveIncomeTaxRateReconciliationAdjustmentsToUncertainAndEffectiveSettledTaxPositionsNetAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationAdjustmentsToUncertainAndEffectiveSettledTaxPositionsNetAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EffectiveIncomeTaxRateReconciliationTaxCreditFederalAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationTaxCreditFederalAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EffectiveIncomeTaxRateReconciliationInternalCorporateReorganizationAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationInternalCorporateReorganizationAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_DeferredTaxAssetsOperatingLossAndOtherLossCarryforwards" abstract="false" name="DeferredTaxAssetsOperatingLossAndOtherLossCarryforwards" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_DeferredTaxAssetsAdvanceOnSaleOfInvestment" abstract="false" name="DeferredTaxAssetsAdvanceOnSaleOfInvestment" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_DeferredTaxLiabilitiesPropertyPlantAndEquipmentAndIntangibleAssets" abstract="false" name="DeferredTaxLiabilitiesPropertyPlantAndEquipmentAndIntangibleAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_DeferredTaxLiabilitiesDebt" abstract="false" name="DeferredTaxLiabilitiesDebt" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_ChangesInTheValuationAllowanceForDeferredTaxAssetsValuationAllowanceRollForward" abstract="true" name="ChangesInTheValuationAllowanceForDeferredTaxAssetsValuationAllowanceRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cmcsa_ValuationAllowanceDeferredTaxAssetAdditionsChargedToIncomeTaxExpenseAndOtherAccounts" abstract="false" name="ValuationAllowanceDeferredTaxAssetAdditionsChargedToIncomeTaxExpenseAndOtherAccounts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_ValuationAllowanceDeferredTaxAssetDeductionsFromReserves" abstract="false" name="ValuationAllowanceDeferredTaxAssetDeductionsFromReserves" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_CapitalLossCarryforwardFederalInternalCorporateReorganizationMember" abstract="true" name="CapitalLossCarryforwardFederalInternalCorporateReorganizationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_IncomeTaxesLineItems" abstract="true" name="IncomeTaxesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cmcsa_ChangesInNetDeferredTaxLiabilityRelatedToOtherComprehensiveIncome" abstract="false" name="ChangesInNetDeferredTaxLiabilityRelatedToOtherComprehensiveIncome" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_IncomeTaxesReceivableFederalCurrent" abstract="false" name="IncomeTaxesReceivableFederalCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_MaturingInFiveYearsOrLessMember" abstract="true" name="MaturingInFiveYearsOrLessMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_MaturingBetweenFiveAndTenYearsMember" abstract="true" name="MaturingBetweenFiveAndTenYearsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_MaturingInGreaterThan10YearsMember" abstract="true" name="MaturingInGreaterThan10YearsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_UniversalBeijingResortTermLoansMember" abstract="true" name="UniversalBeijingResortTermLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_ForeignCurrencyDenominatedSeniorNotesAndTermLoansMemberMember" abstract="true" name="ForeignCurrencyDenominatedSeniorNotesAndTermLoansMemberMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_FinanceLeaseObligationAndOther" abstract="false" name="FinanceLeaseObligationAndOther" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_DebtIssuanceCostsPremiumsDiscountsAndFairValueAdjustmentsForAcquisitionAccountingAndHedgedPositions" abstract="false" name="DebtIssuanceCostsPremiumsDiscountsAndFairValueAdjustmentsForAcquisitionAccountingAndHedgedPositions" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_RevolvingCreditFacilityDueMay172029Member" abstract="true" name="RevolvingCreditFacilityDueMay172029Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_LettersOfCreditAndBankGuaranteesOutstandingAmount" abstract="false" name="LettersOfCreditAndBankGuaranteesOutstandingAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_ForeignCurrencyDenominatedIntercompanyLoansMember" abstract="true" name="ForeignCurrencyDenominatedIntercompanyLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_AmountOfNetInvestmentInForeignSubsidiariesHedged" abstract="false" name="AmountOfNetInvestmentInForeignSubsidiariesHedged" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_ForeignCurrencyDenominatedDebtObligationsAndIntercompanyFundingArrangementsDenominatedInACurrencyOtherThanFunctionalMember" abstract="true" name="ForeignCurrencyDenominatedDebtObligationsAndIntercompanyFundingArrangementsDenominatedInACurrencyOtherThanFunctionalMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_AtairosMember" abstract="true" name="AtairosMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_HuluMember" abstract="true" name="HuluMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_ShortTermInstrumentsMember" abstract="true" name="ShortTermInstrumentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_UniversalBeijingResortMember" abstract="true" name="UniversalBeijingResortMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_EquityMethodInvestmentInvestmentTerm" abstract="false" name="EquityMethodInvestmentInvestmentTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="cmcsa_EquityMethodInvestmentFundingCommitment" abstract="false" name="EquityMethodInvestmentFundingCommitment" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EquityMethodInvestmentAnnualCapitalCallsMaximumAmount" abstract="false" name="EquityMethodInvestmentAnnualCapitalCallsMaximumAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EquityMethodInvestmentManagementFeeFundingCommitment" abstract="false" name="EquityMethodInvestmentManagementFeeFundingCommitment" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EquityMethodInvestmentFundingCommitmentByManagementCompanyInvestors" abstract="false" name="EquityMethodInvestmentFundingCommitmentByManagementCompanyInvestors" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EquityMethodInvestmentPercentOfLosses" abstract="false" name="EquityMethodInvestmentPercentOfLosses" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="cmcsa_PercentageOfResidualReturns" abstract="false" name="PercentageOfResidualReturns" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="cmcsa_VariableInterestEntityReportingEntityInvolvementUnfundedCapitalCommitment" abstract="false" name="VariableInterestEntityReportingEntityInvolvementUnfundedCapitalCommitment" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_CapitalContributionToVIE" abstract="false" name="CapitalContributionToVIE" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EquityMethodInvestmentsAndCertainRetainedDistributions" abstract="false" name="EquityMethodInvestmentsAndCertainRetainedDistributions" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EquityMethodInvestmentFairMarketValueFloorForPutAndCallOption" abstract="false" name="EquityMethodInvestmentFairMarketValueFloorForPutAndCallOption" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EquityMethodInvestmentOwnershipPercentageRepresentingFairMarketValueFloorForPutAndCallOption" abstract="false" name="EquityMethodInvestmentOwnershipPercentageRepresentingFairMarketValueFloorForPutAndCallOption" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="cmcsa_AdvanceOnSaleOfInvestmentGross" abstract="false" name="AdvanceOnSaleOfInvestmentGross" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EquityMethodInvestmentsPriorCapitalCallsPaid" abstract="false" name="EquityMethodInvestmentsPriorCapitalCallsPaid" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EquityMethodInvestmentFutureTaxBenefitsShared" abstract="false" name="EquityMethodInvestmentFutureTaxBenefitsShared" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="cmcsa_ProceedsFromCollateralizedObligation" abstract="false" name="ProceedsFromCollateralizedObligation" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_DistributionSystemMember" abstract="true" name="DistributionSystemMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_CustomerPremiseEquipmentMember" abstract="true" name="CustomerPremiseEquipmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_BuildingsThemeParkInfrastructureAndLeaseholdImprovementsMember" abstract="true" name="BuildingsThemeParkInfrastructureAndLeaseholdImprovementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_CableCommunicationsSegmentsMember" abstract="true" name="CableCommunicationsSegmentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_SkyLimitedSegmentMember" abstract="true" name="SkyLimitedSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_GoodwillForeignCurrencyTranslationGainLossAndOther" abstract="false" name="GoodwillForeignCurrencyTranslationGainLossAndOther" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_DeferredCompensationPlansMember" abstract="true" name="DeferredCompensationPlansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="cmcsa_DeferredCompensationPlansInterestCost" abstract="false" name="DeferredCompensationPlansInterestCost" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_CommonStockVotingPower" abstract="false" name="CommonStockVotingPower" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="cmcsa_NumberOfVotesEntitledOfEachClassBCommonStock" abstract="false" name="NumberOfVotesEntitledOfEachClassBCommonStock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:positiveIntegerItemType"/>
  <xs:element id="cmcsa_PaymentForPurchasesOfThirdPartyTransferableTaxCredits" abstract="false" name="PaymentForPurchasesOfThirdPartyTransferableTaxCredits" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_OperatingLeaseExpenseInclusiveOfShortTermAndVariableLeaseExpenses" abstract="false" name="OperatingLeaseExpenseInclusiveOfShortTermAndVariableLeaseExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_CarryingValueOfContractualObligation" abstract="false" name="CarryingValueOfContractualObligation" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_ContractualValueOfAPotentialFutureObligation" abstract="false" name="ContractualValueOfAPotentialFutureObligation" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
