content: <?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:com="http://www.sec.gov/edgar/common">
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      <submissionType>144</submissionType>
      <filerInfo>
        <filer>
          <filerCredentials>
            <cik>0001533913</cik>
            <ccc>XXXXXXXX</ccc>
          </filerCredentials>
        </filer>
        <liveTestFlag>LIVE</liveTestFlag>
  
  
  
      </filerInfo>
    </headerData>
    <formData>
      <issuerInfo>
        <issuerCik>0001973239</issuerCik>
        <issuerName>ARM HOLDINGS PLC /UK</issuerName>
        <secFileNumber>001-41800</secFileNumber>
        <issuerAddress>
          <com:street1>110 FULBOURN ROAD</com:street1>
          <com:city>CAMBRIDGE</com:city>
          <com:stateOrCountry>X0</com:stateOrCountry>
          <com:zipCode>CB1 9NJ</com:zipCode>
        </issuerAddress>
        <issuerContactPhone>44 1223 400 400</issuerContactPhone>
        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Child Jason</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>Officer</relationshipToIssuer>
        </relationshipsToIssuer>
      </issuerInfo>
      <securitiesInformation>
        <securitiesClassTitle>American Depository Receipt</securitiesClassTitle>
        <brokerOrMarketmakerDetails>
          <name>Fidelity Brokerage Services LLC</name>
          <address>
            <com:street1>900 Salem Street</com:street1>
            <com:city>Smithfield</com:city>
            <com:stateOrCountry>RI</com:stateOrCountry>
            <com:zipCode>02917</com:zipCode>
          </address>
        </brokerOrMarketmakerDetails>
        <noOfUnitsSold>9220</noOfUnitsSold>
        <aggregateMarketValue>1412504.00</aggregateMarketValue>
        <noOfUnitsOutstanding>1040330497</noOfUnitsOutstanding>
        <approxSaleDate>02/20/2025</approxSaleDate>
        <securitiesExchangeName>NASDAQ</securitiesExchangeName>
      </securitiesInformation>
      <securitiesToBeSold>
        <securitiesClassTitle>American Depository Receipt</securitiesClassTitle>
        <acquiredDate>11/15/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>6737</amountOfSecuritiesAcquired>
        <paymentDate>11/15/2023</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>American Depository Receipt</securitiesClassTitle>
        <acquiredDate>02/15/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>2483</amountOfSecuritiesAcquired>
        <paymentDate>02/15/2024</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
      <securitiesSoldInPast3Months>
        <sellerDetails>
          <name>Jason E. Child</name>
          <address>
            <com:street1>110 Fulbourn Road</com:street1>
            <com:city>Cambridge</com:city>
            <com:stateOrCountry>X0</com:stateOrCountry>
            <com:zipCode>CB1 9NJ</com:zipCode>
          </address>
        </sellerDetails>
        <securitiesClassTitle>American Depository Receipt</securitiesClassTitle>
        <saleDate>11/21/2024</saleDate>
        <amountOfSecuritiesSold>20160</amountOfSecuritiesSold>
        <grossProceeds>2751840.00</grossProceeds>
      </securitiesSoldInPast3Months>
      <securitiesSoldInPast3Months>
        <sellerDetails>
          <name>Jason E. Child</name>
          <address>
            <com:street1>110 Fulbourn Road</com:street1>
            <com:city>Cambridge</com:city>
            <com:stateOrCountry>X0</com:stateOrCountry>
            <com:zipCode>CB1 9NJ</com:zipCode>
          </address>
        </sellerDetails>
        <securitiesClassTitle>American Depository Receipt</securitiesClassTitle>
        <saleDate>01/22/2025</saleDate>
        <amountOfSecuritiesSold>10080</amountOfSecuritiesSold>
        <grossProceeds>1764000.00</grossProceeds>
      </securitiesSoldInPast3Months>
      <noticeSignature>
        <noticeDate>02/20/2025</noticeDate>
        <planAdoptionDates>
          <planAdoptionDate>08/09/2024</planAdoptionDate>
        </planAdoptionDates>
        <signature>/s/ Joshua Schmitt, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Jason E. Child.</signature>
      </noticeSignature>
    </formData>
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text: 144
  0001533913
  XXXXXXXX
  LIVE
  0001973239
  ARM HOLDINGS PLC /UK
  001-41800
  110 FULBOURN ROAD
  CAMBRIDGE
  X0
  CB1 9NJ
  44 1223 400 400
  Child Jason
  Officer
  American Depository Receipt
  Fidelity Brokerage Services LLC
  900 Salem Street
  Smithfield
  RI
  02917
  9220
  1412504.00
  1040330497
  02/20/2025
  NASDAQ
  American Depository Receipt
  11/15/2023
  Restricted Stock Vesting
  Issuer
  N
  6737
  11/15/2023
  Compensation
  American Depository Receipt
  02/15/2024
  Restricted Stock Vesting
  Issuer
  N
  2483
  02/15/2024
  Compensation
  N
  Jason E. Child
  110 Fulbourn Road
  Cambridge
  X0
  CB1 9NJ
  American Depository Receipt
  11/21/2024
  20160
  2751840.00
  Jason E. Child
  110 Fulbourn Road
  Cambridge
  X0
  CB1 9NJ
  American Depository Receipt
  01/22/2025
  10080
  1764000.00
  02/20/2025
  08/09/2024
  /s/ Joshua Schmitt, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Jason E. Child.