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            <!-- Field: Pseudo-Tag; ID: Name; Data: Hazell David Arthur -->
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            <ccc>XXXXXXXX</ccc>
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        <liveTestFlag>LIVE</liveTestFlag>
  
  
  
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        <issuerCik>0000891478</issuerCik>
        <issuerName>Banco Santander, S.A.</issuerName>
        <secFileNumber>001-12518</secFileNumber>
        <issuerAddress>
          <com:street1>Ciudad Grupo Santander</com:street1>
          <com:street2>Boadilla del Monte</com:street2>
          <com:city>Madrid</com:city>
          <com:stateOrCountry>U3</com:stateOrCountry>
          <com:zipCode>28660</com:zipCode>
        </issuerAddress>
        <issuerContactPhone>34-91-259-6520</issuerContactPhone>
        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>David Hazell</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>Chief Compliance Officer</relationshipToIssuer>
        </relationshipsToIssuer>
      </issuerInfo>
      <securitiesInformation>
        <securitiesClassTitle>American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each</securitiesClassTitle>
        <brokerOrMarketmakerDetails>
          <name>Fidelity Brokerage Services LLC</name>
          <address>
            <com:street1>PO Box 28019</com:street1>
            <com:city>Albuquerque</com:city>
            <com:stateOrCountry>NM</com:stateOrCountry>
            <com:zipCode>87124</com:zipCode>
          </address>
        </brokerOrMarketmakerDetails>
        <noOfUnitsSold>4370</noOfUnitsSold>
        <aggregateMarketValue>34610.00</aggregateMarketValue>
        <noOfUnitsOutstanding>15152492322</noOfUnitsOutstanding>
        <approxSaleDate>05/13/2025</approxSaleDate>
        <securitiesExchangeName>NYSE</securitiesExchangeName>
      </securitiesInformation>
      <securitiesInformation>
        <securitiesClassTitle>American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each</securitiesClassTitle>
        <brokerOrMarketmakerDetails>
          <name>Fidelity Brokerage Services LLC</name>
          <address>
            <com:street1>PO Box 28019</com:street1>
            <com:city>Albuquerque</com:city>
            <com:stateOrCountry>NM</com:stateOrCountry>
            <com:zipCode>87124</com:zipCode>
          </address>
        </brokerOrMarketmakerDetails>
        <noOfUnitsSold>36660</noOfUnitsSold>
        <aggregateMarketValue>290347.00</aggregateMarketValue>
        <noOfUnitsOutstanding>15152492322</noOfUnitsOutstanding>
        <approxSaleDate>05/13/2025</approxSaleDate>
        <securitiesExchangeName>NYSE</securitiesExchangeName>
      </securitiesInformation>
      <securitiesToBeSold>
        <securitiesClassTitle>American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each</securitiesClassTitle>
        <acquiredDate>03/26/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Equity compensation under the 2021 plan</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>3494</amountOfSecuritiesAcquired>
        <paymentDate>03/26/2024</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each</securitiesClassTitle>
        <acquiredDate>03/14/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Equity compensation under the 2021 plan</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>3747</amountOfSecuritiesAcquired>
        <paymentDate>03/14/2024</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each</securitiesClassTitle>
        <acquiredDate>03/14/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Equity compensation under the 2024 plan</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>20637</amountOfSecuritiesAcquired>
        <paymentDate>03/14/2024</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each</securitiesClassTitle>
        <acquiredDate>03/14/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Equity compensation under the 2023 plan</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>4118</amountOfSecuritiesAcquired>
        <paymentDate>03/14/2024</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each</securitiesClassTitle>
        <acquiredDate>03/14/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Equity compensation under the 2022 plan</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>5541</amountOfSecuritiesAcquired>
        <paymentDate>03/14/2024</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each</securitiesClassTitle>
        <acquiredDate>04/27/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Equity compensation under the 2021 plan</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>3493</amountOfSecuritiesAcquired>
        <paymentDate>04/27/2023</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
      <securitiesSoldInPast3Months>
        <sellerDetails>
          <name>David Hazell</name>
          <address>
            <com:street1>Ciudad Grupo Santander</com:street1>
            <com:street2>Boadilla del Monte</com:street2>
            <com:city>Madrid</com:city>
            <com:stateOrCountry>U3</com:stateOrCountry>
            <com:zipCode>28660</com:zipCode>
          </address>
        </sellerDetails>
        <securitiesClassTitle>Crest Depository Interests (CDIs), each representing one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each.</securitiesClassTitle>
        <saleDate>05/13/2025</saleDate>
        <amountOfSecuritiesSold>1132</amountOfSecuritiesSold>
        <grossProceeds>6544.23</grossProceeds>
      </securitiesSoldInPast3Months>
      <noticeSignature>
        <noticeDate>05/26/2025</noticeDate>
        <signature>/s/ David Hazell</signature>
      </noticeSignature>
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text: 144
  0002069917
  XXXXXXXX
  LIVE
  0000891478
  Banco Santander, S.A.
  001-12518
  Ciudad Grupo Santander
  Boadilla del Monte
  Madrid
  U3
  28660
  34-91-259-6520
  David Hazell
  Chief Compliance Officer
  American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each
  Fidelity Brokerage Services LLC
  PO Box 28019
  Albuquerque
  NM
  87124
  4370
  34610.00
  15152492322
  05/13/2025
  NYSE
  American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each
  Fidelity Brokerage Services LLC
  PO Box 28019
  Albuquerque
  NM
  87124
  36660
  290347.00
  15152492322
  05/13/2025
  NYSE
  American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each
  03/26/2024
  Equity compensation under the 2021 plan
  Issuer
  N
  3494
  03/26/2024
  Compensation
  American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each
  03/14/2024
  Equity compensation under the 2021 plan
  Issuer
  N
  3747
  03/14/2024
  Compensation
  American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each
  03/14/2024
  Equity compensation under the 2024 plan
  Issuer
  N
  20637
  03/14/2024
  Compensation
  American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each
  03/14/2024
  Equity compensation under the 2023 plan
  Issuer
  N
  4118
  03/14/2024
  Compensation
  American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each
  03/14/2024
  Equity compensation under the 2022 plan
  Issuer
  N
  5541
  03/14/2024
  Compensation
  American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each
  04/27/2023
  Equity compensation under the 2021 plan
  Issuer
  N
  3493
  04/27/2023
  Compensation
  N
  David Hazell
  Ciudad Grupo Santander
  Boadilla del Monte
  Madrid
  U3
  28660
  Crest Depository Interests (CDIs), each representing one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each.
  05/13/2025
  1132
  6544.23
  05/26/2025
  /s/ David Hazell