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  <xs:element id="cmcsa_Notes0000PercentDue2026Member" abstract="true" name="Notes0000PercentDue2026Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_Notes0.750percentdue2032Member" abstract="true" name="Notes0.750percentdue2032Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_DeferredTaxLiabilitiesPropertyPlantAndEquipmentAndIntangibleAssets" abstract="false" name="DeferredTaxLiabilitiesPropertyPlantAndEquipmentAndIntangibleAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_StudiosMember" abstract="true" name="StudiosMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_ScheduleOfOtherBalanceSheetAccountsTableTextBlock" abstract="false" name="ScheduleOfOtherBalanceSheetAccountsTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="cmcsa_Notes0250PercentDue2029Member" abstract="true" name="Notes0250PercentDue2029Member" 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_BuildingsThemeParkInfrastructureAndLeaseholdImprovementsMember" abstract="true" name="BuildingsThemeParkInfrastructureAndLeaseholdImprovementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_SupplementalFinancialInformationLineItems" abstract="true" name="SupplementalFinancialInformationLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cmcsa_ResidentialVideoMember" abstract="true" name="ResidentialVideoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_StudiosAndMediaMember" abstract="true" name="StudiosAndMediaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_PaymentsToAcquireIntangibleAssetsSpectrumRights" abstract="false" name="PaymentsToAcquireIntangibleAssetsSpectrumRights" nillable="true" xbrli:periodType="duration" 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:element id="cmcsa_EquityMethodInvestmentOwnershipPercentageRepresentingFairMarketValueFloorForPutAndCallOption" abstract="false" name="EquityMethodInvestmentOwnershipPercentageRepresentingFairMarketValueFloorForPutAndCallOption" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <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_AtairosMember" abstract="true" name="AtairosMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_CommitmentAndContingenciesLineItems" abstract="true" name="CommitmentAndContingenciesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cmcsa_AccountsReceivableAllowanceForCreditLossAdditionsChargedToCostsAndExpensesAndOtherAccounts" abstract="false" name="AccountsReceivableAllowanceForCreditLossAdditionsChargedToCostsAndExpensesAndOtherAccounts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" 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_FilmMonetizedOnItsOwnAndEntertainmentLicenseAgreementForProgramMaterialIncludingSportsRightsAdvancesCapitalizedCostsNoncurrent" abstract="false" name="FilmMonetizedOnItsOwnAndEntertainmentLicenseAgreementForProgramMaterialIncludingSportsRightsAdvancesCapitalizedCostsNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_SeniorNotesWithMaturitiesBetween5And10YearsatfacevalueMember" abstract="true" name="SeniorNotesWithMaturitiesBetween5And10YearsatfacevalueMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_ScheduleOfCurrentAndNoncurrentAssetsAndLiabilitiesTableTextBlock" abstract="false" name="ScheduleOfCurrentAndNoncurrentAssetsAndLiabilitiesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="cmcsa_OtherComprehensiveIncomeLossDefinedBenefitPlanAndOtherAfterReclassificationAdjustmentTax" abstract="false" name="OtherComprehensiveIncomeLossDefinedBenefitPlanAndOtherAfterReclassificationAdjustmentTax" nillable="true" xbrli:periodType="duration" 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_ForeignCurrencyDenominatedNotesAndTermLoansMember" abstract="true" name="ForeignCurrencyDenominatedNotesAndTermLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_UniversalBeijingResortMember" abstract="true" name="UniversalBeijingResortMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_GainLossOnInvestmentsAndOtherNoncashIncomeLossNet" abstract="false" name="GainLossOnInvestmentsAndOtherNoncashIncomeLossNet" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_LicenseAgreementCommitmentsSportsRightsUnrecordedFutureMinimumAmount" abstract="false" name="LicenseAgreementCommitmentsSportsRightsUnrecordedFutureMinimumAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_Increasedecreaseinfilmandtelevisioncostnet" abstract="false" name="Increasedecreaseinfilmandtelevisioncostnet" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_SeniorNotesWithMaturitiesOf5YearsOrLessatFaceValueMember" abstract="true" name="SeniorNotesWithMaturitiesOf5YearsOrLessatFaceValueMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_Notes1.500percentDue2029Member" abstract="true" name="Notes1.500percentDue2029Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_ChangesInTheValuationAllowanceForDeferredTaxAssetsValuationAllowanceRollForward" abstract="true" name="ChangesInTheValuationAllowanceForDeferredTaxAssetsValuationAllowanceRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cmcsa_DeferredCompensationPlansTableTextBlock" abstract="false" name="DeferredCompensationPlansTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="cmcsa_LeaseArrangementsAxis" abstract="true" name="LeaseArrangementsAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <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_DeferredTaxAssetsOperatingLossAndOtherLossCarryforwards" abstract="false" name="DeferredTaxAssetsOperatingLossAndOtherLossCarryforwards" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" 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-types:domainItemType"/>
  <xs:element id="cmcsa_NumberOfBusinesses" abstract="false" name="NumberOfBusinesses" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="cmcsa_NbcuniversalEnterpriseMember" abstract="true" name="NbcuniversalEnterpriseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_ChangesInNetDeferredTaxLiabilityRelatedToOtherComprehensiveIncome" abstract="false" name="ChangesInNetDeferredTaxLiabilityRelatedToOtherComprehensiveIncome" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_CableCommunicationsMember" abstract="true" name="CableCommunicationsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_EquityTable" abstract="true" name="EquityTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="cmcsa_TermLoansMember" abstract="true" name="TermLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_ContentMember" abstract="true" name="ContentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_ExchangeableSubordinatedDebentures2.0PercentDue2029Member" abstract="true" name="ExchangeableSubordinatedDebentures2.0PercentDue2029Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_MediaMember" abstract="true" name="MediaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_UniversalBeijingResortTermLoansMember" abstract="true" name="UniversalBeijingResortTermLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_ChangeInCurrentAndNoncurrentReceivablesNet" abstract="false" name="ChangeInCurrentAndNoncurrentReceivablesNet" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_SignificantTransactionsTextBlock" abstract="false" name="SignificantTransactionsTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="cmcsa_TheatricalMember" abstract="true" name="TheatricalMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_GainLossRelatedToLegalSettlementMember" abstract="true" name="GainLossRelatedToLegalSettlementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_Notes0.250percentDue2027Member" abstract="true" name="Notes0.250percentDue2027Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_RevenuePerformanceObligationDescriptionOfPaymentTermsPeriod" abstract="false" name="RevenuePerformanceObligationDescriptionOfPaymentTermsPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="cmcsa_CapitalCostsIncurredButNotYetPaid" abstract="false" name="CapitalCostsIncurredButNotYetPaid" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_EquityLineItems" abstract="true" name="EquityLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cmcsa_EntertainmentLicenseAgreementForProgramMaterialsUnrecordedFutureMinimumAmount" abstract="false" name="EntertainmentLicenseAgreementForProgramMaterialsUnrecordedFutureMinimumAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_ContentLicensingMember" abstract="true" name="ContentLicensingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_EquityMethodInvestmentMinimumGuaranteedProceedsFloorForPutAndCallOption" abstract="false" name="EquityMethodInvestmentMinimumGuaranteedProceedsFloorForPutAndCallOption" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_ATTInc.Member" abstract="true" name="ATTInc.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsTableTextBlock" abstract="false" name="ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <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_VideoDistributionProgrammingExpense" abstract="false" name="VideoDistributionProgrammingExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_SupplementalFinancialInformationTable" abstract="true" name="SupplementalFinancialInformationTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="cmcsa_TemporaryEquityRedemptionOfPreferredStock" abstract="false" name="TemporaryEquityRedemptionOfPreferredStock" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_LeaseArrangementsDomain" abstract="true" name="LeaseArrangementsDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_InvestmentSecuringCollateralizedObligation" abstract="false" name="InvestmentSecuringCollateralizedObligation" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_ForeignCurrencyDenominatedDebtMember" abstract="true" name="ForeignCurrencyDenominatedDebtMember" 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-types:domainItemType"/>
  <xs:element id="cmcsa_BusinessServicesMember" abstract="true" name="BusinessServicesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_SeniorNotesWithMaturitiesGreaterThan10YearsatfacevalueMember" abstract="true" name="SeniorNotesWithMaturitiesGreaterThan10YearsatfacevalueMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_ScheduleOfCashCashEquivalentsAndRestrictedCashTableTextBlock" abstract="false" name="ScheduleOfCashCashEquivalentsAndRestrictedCashTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="cmcsa_DeferredTaxLiabilitiesLongTermDebt" abstract="false" name="DeferredTaxLiabilitiesLongTermDebt" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_EquityMethodInvestmentMaximumTotalCapitalCallInAnnualPeriod" abstract="false" name="EquityMethodInvestmentMaximumTotalCapitalCallInAnnualPeriod" 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_LettersOfCreditAndBankGuaranteesOutstandingAmount" abstract="false" name="LettersOfCreditAndBankGuaranteesOutstandingAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_AccruedParticipationsAndResidualsCurrent" abstract="false" name="AccruedParticipationsAndResidualsCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_ComponentsOfInvestmentAndOtherIncomeLossNetTableTextBlock" abstract="false" name="ComponentsOfInvestmentAndOtherIncomeLossNetTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="cmcsa_EquityMethodInvestmentInvestmentTerm" abstract="false" name="EquityMethodInvestmentInvestmentTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <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_AdjustedEBITDA" abstract="false" name="AdjustedEBITDA" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_OtherIncomeLossNet" abstract="false" name="OtherIncomeLossNet" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_CollateralizedObligation" abstract="false" name="CollateralizedObligation" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_DeferredTaxLiabilityInvestments" abstract="false" name="DeferredTaxLiabilityInvestments" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_HuluMember" abstract="true" name="HuluMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_NetIncomeLossAttributableToNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock" abstract="false" name="NetIncomeLossAttributableToNoncontrollingInterestsAndRedeemableSubsidiaryPreferredStock" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_FilmCostsAndEntertainmentEntitiesPolicyPolicyTextBlock" abstract="false" name="FilmCostsAndEntertainmentEntitiesPolicyPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="cmcsa_EquityMethodInvestmentOwnershipPercentageFloor" abstract="false" name="EquityMethodInvestmentOwnershipPercentageFloor" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="cmcsa_DirectToConsumerMember" abstract="true" name="DirectToConsumerMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_CollateralizedObligationFairValue" abstract="false" name="CollateralizedObligationFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_AccountsReceivableAllowanceForCreditLossDeductionsFromReserves" abstract="false" name="AccountsReceivableAllowanceForCreditLossDeductionsFromReserves" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_HomeEntertainmentAndOtherMember" abstract="true" name="HomeEntertainmentAndOtherMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_TotalIntersegmentEliminationsMember" abstract="true" name="TotalIntersegmentEliminationsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_FinanceLeaseObligationsAndOtherMember" abstract="true" name="FinanceLeaseObligationsAndOtherMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_ScheduleOfProgrammingAndProductionCostTableTextBlock" abstract="false" name="ScheduleOfProgrammingAndProductionCostTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <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_DeferredCompensationPlansBenefitObligation" abstract="false" name="DeferredCompensationPlansBenefitObligation" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_Notes5.50PercentDue2029Member" abstract="true" name="Notes5.50PercentDue2029Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_NumberOfVotesEntitledOfEachClassBCommonStock" abstract="false" name="NumberOfVotesEntitledOfEachClassBCommonStock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:positiveIntegerItemType"/>
  <xs:element id="cmcsa_NBCUniversalSegmentsMember" abstract="true" name="NBCUniversalSegmentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_ResidentialBroadbandMember" abstract="true" name="ResidentialBroadbandMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_NumberOfPreferredStockSeries" abstract="false" name="NumberOfPreferredStockSeries" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <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_CableNetworksMember" abstract="true" name="CableNetworksMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_CorporateNonSegmentIntersegmentRevenueMember" abstract="true" name="CorporateNonSegmentIntersegmentRevenueMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_RevenuePerformanceObligationDescriptionOfTimingTermOfContract" abstract="false" name="RevenuePerformanceObligationDescriptionOfTimingTermOfContract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="cmcsa_SkyLimitedMember" abstract="true" name="SkyLimitedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_AuditInformationAbstract" abstract="true" name="AuditInformationAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <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_AdjustmentsForItemsExcludedFromAdjustedEBITDA" abstract="false" name="AdjustmentsForItemsExcludedFromAdjustedEBITDA" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_LineOfCreditFacilityPotentialIncreaseToMaximumBorrowingCapacity" abstract="false" name="LineOfCreditFacilityPotentialIncreaseToMaximumBorrowingCapacity" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" 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_FilmMonetizedOnItsOwnCapitalizedCostInProductionAndInDevelopment" abstract="false" name="FilmMonetizedOnItsOwnCapitalizedCostInProductionAndInDevelopment" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_FormerCFOMember" abstract="true" name="FormerCFOMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_IncomeTaxesTable" abstract="true" name="IncomeTaxesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="cmcsa_CommitmentAndContingenciesTable" abstract="true" name="CommitmentAndContingenciesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <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_MasergyMember" abstract="true" name="MasergyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_CommonStockVotingPower" abstract="false" name="CommonStockVotingPower" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="cmcsa_NoncashInterestExpenseIncomeNet" abstract="false" name="NoncashInterestExpenseIncomeNet" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_ScheduleOfCapitalizedFilmAndTelevisionCostsTableTextBlock" abstract="false" name="ScheduleOfCapitalizedFilmAndTelevisionCostsTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="cmcsa_CustomerPremiseEquipmentMember" abstract="true" name="CustomerPremiseEquipmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_InvestmentsImpairmentPolicyTextBlock" abstract="false" name="InvestmentsImpairmentPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="cmcsa_PercentageOfResidualReturns" abstract="false" name="PercentageOfResidualReturns" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="cmcsa_BroadcastTelevisionMember" abstract="true" name="BroadcastTelevisionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_DistributionSystemMember" abstract="true" name="DistributionSystemMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_ChangesInNetDeferredTaxLiabilityRelatedToAcquisitions" abstract="false" name="ChangesInNetDeferredTaxLiabilityRelatedToAcquisitions" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" 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_Notes1.250percentdue2040Member" abstract="true" name="Notes1.250percentdue2040Member" 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_AmountOfForeignCurrencyDenominatedDebtHedged" abstract="false" name="AmountOfForeignCurrencyDenominatedDebtHedged" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPlanAndOtherAfterTax" abstract="false" name="AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPlanAndOtherAfterTax" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmcsa_ResidentialWirelessMember" abstract="true" name="ResidentialWirelessMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmcsa_PaymentsForRepurchaseAndRedemptionOfSubsidiaryPreferredStock" abstract="false" name="PaymentsForRepurchaseAndRedemptionOfSubsidiaryPreferredStock" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
