content: <?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:com="http://www.sec.gov/edgar/common">
    <headerData>
      <submissionType>144</submissionType>
      <filerInfo>
        <filer>
          <filerCredentials>
            <cik>0001999165</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>Collins Spencer</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>Officer</relationshipToIssuer>
        </relationshipsToIssuer>
      </issuerInfo>
      <securitiesInformation>
        <securitiesClassTitle>American Depositary Shares</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>51960</noOfUnitsSold>
        <aggregateMarketValue>7430280.00</aggregateMarketValue>
        <noOfUnitsOutstanding>1040330497</noOfUnitsOutstanding>
        <approxSaleDate>09/16/2024</approxSaleDate>
        <securitiesExchangeName>NASDAQ</securitiesExchangeName>
      </securitiesInformation>
      <securitiesToBeSold>
        <securitiesClassTitle>American Depositary Shares</securitiesClassTitle>
        <acquiredDate>09/14/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>51960</amountOfSecuritiesAcquired>
        <paymentDate>09/14/2024</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
      <noticeSignature>
        <noticeDate>09/16/2024</noticeDate>
        <signature>/s/ Eric Janiak, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Spencer Collins</signature>
      </noticeSignature>
    </formData>
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text: 144
  0001999165
  XXXXXXXX
  LIVE
  0001973239
  ARM HOLDINGS PLC /UK
  001-41800
  110 FULBOURN ROAD
  CAMBRIDGE
  X0
  CB1 9NJ
  44 1223 400 400
  Collins Spencer
  Officer
  American Depositary Shares
  Fidelity Brokerage Services LLC
  900 Salem Street
  Smithfield
  RI
  02917
  51960
  7430280.00
  1040330497
  09/16/2024
  NASDAQ
  American Depositary Shares
  09/14/2024
  Restricted Stock Vesting
  Issuer
  N
  51960
  09/14/2024
  Compensation
  Y
  09/16/2024
  /s/ Eric Janiak, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Spencer Collins