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>0001967201</cik>
            <ccc>XXXXXXXX</ccc>
          </filerCredentials>
        </filer>
        <liveTestFlag>LIVE</liveTestFlag>
  
  
  
      </filerInfo>
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      <issuerInfo>
        <issuerCik>0001859690</issuerCik>
        <issuerName>Arqit Quantum Inc.</issuerName>
        <secFileNumber>001-40777</secFileNumber>
        <issuerAddress>
          <com:street1>NOVA NORTH</com:street1>
          <com:street2>7 FLOOR, 11 BRESSENDEN PLACE</com:street2>
          <com:city>LONDON</com:city>
          <com:stateOrCountry>X0</com:stateOrCountry>
          <com:zipCode>SW1E 5BY</com:zipCode>
        </issuerAddress>
        <issuerContactPhone>44 203 91 70155</issuerContactPhone>
        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Pointon Nicholas</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>Officer</relationshipToIssuer>
          <relationshipToIssuer>Director</relationshipToIssuer>
        </relationshipsToIssuer>
      </issuerInfo>
      <securitiesInformation>
        <securitiesClassTitle>Common</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>1162</noOfUnitsSold>
        <aggregateMarketValue>505.35</aggregateMarketValue>
        <noOfUnitsOutstanding>163554269</noOfUnitsOutstanding>
        <approxSaleDate>01/04/2024</approxSaleDate>
        <securitiesExchangeName>NASDAQ</securitiesExchangeName>
      </securitiesInformation>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>01/03/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>1162</amountOfSecuritiesAcquired>
        <paymentDate>01/03/2024</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
      <securitiesSoldInPast3Months>
        <sellerDetails>
          <name>Nicholas Pointon</name>
          <address>
            <com:street1>Nova North, 7 Floor, 11 Bressenden Place</com:street1>
            <com:city>London</com:city>
            <com:stateOrCountry>X0</com:stateOrCountry>
            <com:zipCode>SW1E 5BY</com:zipCode>
          </address>
        </sellerDetails>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <saleDate>10/04/2023</saleDate>
        <amountOfSecuritiesSold>1126</amountOfSecuritiesSold>
        <grossProceeds>630.56</grossProceeds>
      </securitiesSoldInPast3Months>
      <securitiesSoldInPast3Months>
        <sellerDetails>
          <name>Nicholas Pointon</name>
          <address>
            <com:street1>Nova North, 7 Floor, 11 Bressenden Place</com:street1>
            <com:city>London</com:city>
            <com:stateOrCountry>X0</com:stateOrCountry>
            <com:zipCode>SW1E 5BY</com:zipCode>
          </address>
        </sellerDetails>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <saleDate>01/03/2024</saleDate>
        <amountOfSecuritiesSold>1214</amountOfSecuritiesSold>
        <grossProceeds>539.62</grossProceeds>
      </securitiesSoldInPast3Months>
      <noticeSignature>
        <noticeDate>01/04/2024</noticeDate>
        <signature>/s/ Daniel Tucci, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Nicholas Pointon</signature>
      </noticeSignature>
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text: 144
  0001967201
  XXXXXXXX
  LIVE
  0001859690
  Arqit Quantum Inc.
  001-40777
  NOVA NORTH
  7 FLOOR, 11 BRESSENDEN PLACE
  LONDON
  X0
  SW1E 5BY
  44 203 91 70155
  Pointon Nicholas
  Officer
  Director
  Common
  Fidelity Brokerage Services LLC
  900 Salem Street
  Smithfield
  RI
  02917
  1162
  505.35
  163554269
  01/04/2024
  NASDAQ
  Common
  01/03/2024
  Restricted Stock Vesting
  Issuer
  N
  1162
  01/03/2024
  Compensation
  N
  Nicholas Pointon
  Nova North, 7 Floor, 11 Bressenden Place
  London
  X0
  SW1E 5BY
  Common
  10/04/2023
  1126
  630.56
  Nicholas Pointon
  Nova North, 7 Floor, 11 Bressenden Place
  London
  X0
  SW1E 5BY
  Common
  01/03/2024
  1214
  539.62
  01/04/2024
  /s/ Daniel Tucci, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Nicholas Pointon