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    <ReturnTs>2026-01-26T17:57:17-05:00</ReturnTs>
    <TaxPeriodEndDt>2025-12-31</TaxPeriodEndDt>
    <ReturnTypeCd>990EZ</ReturnTypeCd>
    <TaxPeriodBeginDt>2025-01-01</TaxPeriodBeginDt>
    <Filer>
      <EIN>237046788</EIN>
      <BusinessName>
        <BusinessNameLine1Txt>CONTRA COSTA REGIONAL MEDICAL CENTER AUXILIARY</BusinessNameLine1Txt>
      </BusinessName>
      <BusinessNameControlTxt>CONT</BusinessNameControlTxt>
      <ForeignPhoneNum>9253705441</ForeignPhoneNum>
      <USAddress>
        <AddressLine1Txt>2500 ALHAMBRA AVE</AddressLine1Txt>
        <CityNm>MARTINEZ</CityNm>
        <StateAbbreviationCd>CA</StateAbbreviationCd>
        <ZIPCd>945533156</ZIPCd>
      </USAddress>
    </Filer>
    <BusinessOfficerGrp>
      <PersonNm>Susan Linnell</PersonNm>
      <PersonTitleTxt>Bookkeeper</PersonTitleTxt>
      <PhoneNum>5105013755</PhoneNum>
      <SignatureDt>2026-01-29</SignatureDt>
    </BusinessOfficerGrp>
    <TaxYr>2025</TaxYr>
    <BuildTS>2025-03-06 01:10:19Z</BuildTS>
  </ReturnHeader>
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      <ScheduleBNotRequiredInd>X</ScheduleBNotRequiredInd>
      <Organization501c3Ind referenceDocumentId="IRS990ScheduleA1" referenceDocumentName="IRS990ScheduleA">X</Organization501c3Ind>
      <TypeOfOrganizationCorpInd>X</TypeOfOrganizationCorpInd>
      <GrossReceiptsAmt>34666</GrossReceiptsAmt>
      <InfoInScheduleOPartIInd>X</InfoInScheduleOPartIInd>
      <ContributionsGiftsGrantsEtcAmt>6815</ContributionsGiftsGrantsEtcAmt>
      <ProgramServiceRevenueAmt>0</ProgramServiceRevenueAmt>
      <MembershipDuesAmt>0</MembershipDuesAmt>
      <InvestmentIncomeAmt>10</InvestmentIncomeAmt>
      <SaleOfAssetsGrossAmt>0</SaleOfAssetsGrossAmt>
      <CostOrOtherBasisExpenseSaleAmt>0</CostOrOtherBasisExpenseSaleAmt>
      <GainOrLossFromSaleOfAssetsAmt>0</GainOrLossFromSaleOfAssetsAmt>
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      <SpecialEventsDirectExpensesAmt>0</SpecialEventsDirectExpensesAmt>
      <SpecialEventsNetIncomeLossAmt>0</SpecialEventsNetIncomeLossAmt>
      <GrossSalesOfInventoryAmt>27841</GrossSalesOfInventoryAmt>
      <CostOfGoodsSoldAmt>19013</CostOfGoodsSoldAmt>
      <GrossProfitLossSlsOfInvntryAmt>8828</GrossProfitLossSlsOfInvntryAmt>
      <TotalRevenueAmt>15653</TotalRevenueAmt>
      <GrantsAndSimilarAmountsPaidAmt>8544</GrantsAndSimilarAmountsPaidAmt>
      <BenefitsPaidToOrForMembersAmt>558</BenefitsPaidToOrForMembersAmt>
      <SalariesOtherCompEmplBnftAmt>0</SalariesOtherCompEmplBnftAmt>
      <FeesAndOtherPymtToIndCntrctAmt>5251</FeesAndOtherPymtToIndCntrctAmt>
      <OccupancyRentUtltsAndMaintAmt>0</OccupancyRentUtltsAndMaintAmt>
      <PrintingPublicationsPostageAmt>0</PrintingPublicationsPostageAmt>
      <OtherExpensesTotalAmt>3539</OtherExpensesTotalAmt>
      <TotalExpensesAmt>17892</TotalExpensesAmt>
      <ExcessOrDeficitForYearAmt>-2239</ExcessOrDeficitForYearAmt>
      <NetAssetsOrFundBalancesBOYAmt>89955</NetAssetsOrFundBalancesBOYAmt>
      <OtherChangesInNetAssetsAmt>1893</OtherChangesInNetAssetsAmt>
      <NetAssetsOrFundBalancesEOYAmt>89609</NetAssetsOrFundBalancesEOYAmt>
      <InfoInScheduleOPartIIInd>X</InfoInScheduleOPartIIInd>
      <CashSavingsAndInvestmentsGrp>
        <BOYAmt>53489</BOYAmt>
        <EOYAmt>47359</EOYAmt>
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      <LandAndBuildingsGrp>
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        <EOYAmt>0</EOYAmt>
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      <OtherAssetsTotalDetail>
        <BOYAmt>37102</BOYAmt>
        <EOYAmt>42906</EOYAmt>
      </OtherAssetsTotalDetail>
      <Form990TotalAssetsGrp>
        <BOYAmt>90591</BOYAmt>
        <EOYAmt>90265</EOYAmt>
      </Form990TotalAssetsGrp>
      <SumOfTotalLiabilitiesGrp>
        <BOYAmt>636</BOYAmt>
        <EOYAmt>656</EOYAmt>
      </SumOfTotalLiabilitiesGrp>
      <NetAssetsOrFundBalancesGrp>
        <BOYAmt>89955</BOYAmt>
        <EOYAmt>89609</EOYAmt>
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      <PrimaryExemptPurposeTxt>THE CONTRA COSTA REGIONAL MEDICAL CENTER AUXILIARYS PURPOSE IS TO PROVIDE SERVICE AND FUNDS FOR SPECIAL PROJECTS WITHIN THE COUNTY HOSPITAL SYSTEM THAT OTHERWISE ARE NOT FUNDED. WITH THE PRIMARY EMPHASIS ON INFANTS AND THE MOST UNDERSERVED IN OUR COMMUNITY.</PrimaryExemptPurposeTxt>
      <ProgramSrvcAccomplishmentGrp>
        <DescriptionProgramSrvcAccomTxt>Layette</DescriptionProgramSrvcAccomTxt>
        <GrantsAndAllocationsAmt>0</GrantsAndAllocationsAmt>
        <ProgramServiceExpensesAmt>5639</ProgramServiceExpensesAmt>
      </ProgramSrvcAccomplishmentGrp>
      <ProgramSrvcAccomplishmentGrp>
        <DescriptionProgramSrvcAccomTxt>Patient Care</DescriptionProgramSrvcAccomTxt>
        <GrantsAndAllocationsAmt>0</GrantsAndAllocationsAmt>
        <ProgramServiceExpensesAmt>682</ProgramServiceExpensesAmt>
      </ProgramSrvcAccomplishmentGrp>
      <ProgramSrvcAccomplishmentGrp>
        <DescriptionProgramSrvcAccomTxt>Cancer $1050 Doula 1173</DescriptionProgramSrvcAccomTxt>
        <GrantsAndAllocationsAmt>0</GrantsAndAllocationsAmt>
        <ProgramServiceExpensesAmt>2223</ProgramServiceExpensesAmt>
      </ProgramSrvcAccomplishmentGrp>
      <TotalProgramServiceExpensesAmt>8544</TotalProgramServiceExpensesAmt>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Linda Waxman</PersonNm>
        <TitleTxt>President</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>5</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Eileen Devlin</PersonNm>
        <TitleTxt>Secretary</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>1</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Skip Weinstock</PersonNm>
        <TitleTxt>Treasurer</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>4</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Betty Holt</PersonNm>
        <TitleTxt>Assistant Treasurer</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>1</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Linda Waxman</PersonNm>
        <TitleTxt>Gift Shop Manager</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>35</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Susan Tunison</PersonNm>
        <TitleTxt>Historian</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>1</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Florence Berghius</PersonNm>
        <TitleTxt>Parliamentarian</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>1</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Pat Harris</PersonNm>
        <TitleTxt>Sunshine</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>1</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Ed Quinnan</PersonNm>
        <TitleTxt>Member at Large</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>1</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <ActivitiesNotPreviouslyRptInd>false</ActivitiesNotPreviouslyRptInd>
      <ChgMadeToOrgnzngDocNotRptInd>false</ChgMadeToOrgnzngDocNotRptInd>
      <OrganizationHadUBIInd>false</OrganizationHadUBIInd>
      <SubjectToProxyTaxInd referenceDocumentName="IRS990ScheduleC">false</SubjectToProxyTaxInd>
      <OrganizationDissolvedEtcInd referenceDocumentName="IRS990ScheduleN BinaryAttachment">false</OrganizationDissolvedEtcInd>
      <DirectIndirectPltclExpendAmt>0</DirectIndirectPltclExpendAmt>
      <Form1120PolFiledInd>false</Form1120PolFiledInd>
      <MadeLoansToFromOfficersInd>false</MadeLoansToFromOfficersInd>
      <EngagedInExcessBenefitTransInd referenceDocumentName="IRS990ScheduleL">false</EngagedInExcessBenefitTransInd>
      <ProhibitedTaxShelterTransInd>false</ProhibitedTaxShelterTransInd>
      <BooksInCareOfDetail>
        <PersonNm>Susan L Linnell</PersonNm>
        <USAddress>
          <AddressLine1Txt>7517 S Quinn Ct</AddressLine1Txt>
          <CityNm>Gilbert</CityNm>
          <StateAbbreviationCd>AZ</StateAbbreviationCd>
          <ZIPCd>852980058</ZIPCd>
        </USAddress>
        <PhoneNum>5105013755</PhoneNum>
      </BooksInCareOfDetail>
      <ForeignFinancialAccountInd>false</ForeignFinancialAccountInd>
      <ForeignOfficeInd>false</ForeignOfficeInd>
      <DonorAdvisedFndsInd>false</DonorAdvisedFndsInd>
      <OperateHospitalInd>false</OperateHospitalInd>
      <TanningServicesProvidedInd>false</TanningServicesProvidedInd>
      <RelatedOrganizationCtrlEntInd>false</RelatedOrganizationCtrlEntInd>
      <TransactionWithControlEntInd>false</TransactionWithControlEntInd>
      <PoliticalCampaignActyInd referenceDocumentName="IRS990ScheduleC">false</PoliticalCampaignActyInd>
      <LobbyingActivitiesInd referenceDocumentName="IRS990ScheduleC">false</LobbyingActivitiesInd>
      <SchoolOperatingInd referenceDocumentName="IRS990ScheduleE">false</SchoolOperatingInd>
      <TrnsfrExmptNonChrtblRltdOrgInd>false</TrnsfrExmptNonChrtblRltdOrgInd>
      <PartVIOfCompOfHghstPdEmplTxt>NONE</PartVIOfCompOfHghstPdEmplTxt>
      <PartVIHghstPdCntrctProfSrvcTxt>NONE</PartVIHghstPdCntrctProfSrvcTxt>
      <FiledScheduleAInd>true</FiledScheduleAInd>
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    <IRS990ScheduleA documentId="IRS990ScheduleA1" documentName="IRS990ScheduleA">
      <HospitalInd>X</HospitalInd>
    </IRS990ScheduleA>
    <IRS990ScheduleO documentId="IRS990ScheduleO1" documentName="IRS990ScheduleO">
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part I, line 10</FormAndLineReferenceDesc>
        <ExplanationTxt>| Grants And Similar Amounts Paid:, Amount:| CANCER, $1050| DOULA PROGRAM, $1173| LAYETTE PROGRAM, $5639| PATIENT CARE, $682|</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part I, line 16</FormAndLineReferenceDesc>
        <ExplanationTxt>| Other Expenses:, Amount:| COMPUTER SOFTWARE, $3135| MERCHANT FEES, $172| TAX FEES AND PENALTIES, $232|</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part I, line 20</FormAndLineReferenceDesc>
        <ExplanationTxt>| Explanation:, Amount:| ADJUSTMENT TO PHYSICAL INVENTORY, $1893|</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part II, line 24</FormAndLineReferenceDesc>
        <ExplanationTxt>| Explanation:, BOYAmount:, EOYAmount:| OTHER ASSETS, $37102, $42906|</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part II, line 26</FormAndLineReferenceDesc>
        <ExplanationTxt>| Explanation:, BOYAmount:, EOYAmount:| TOTAL LIABILITIES, $636, $656|</ExplanationTxt>
      </SupplementalInformationDetail>
    </IRS990ScheduleO>
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