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        <filer>
          <filerCredentials>
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            <ccc>XXXXXXXX</ccc>
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        </filer>
        <liveTestFlag>LIVE</liveTestFlag>
  
  
  
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        <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>Ritchie Garth</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <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>221</noOfUnitsSold>
        <aggregateMarketValue>123.63</aggregateMarketValue>
        <noOfUnitsOutstanding>121926166</noOfUnitsOutstanding>
        <approxSaleDate>10/12/2023</approxSaleDate>
        <securitiesExchangeName>NASDAQ</securitiesExchangeName>
      </securitiesInformation>
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        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>10/02/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>221</amountOfSecuritiesAcquired>
        <paymentDate>10/02/2023</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
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          <name>Garth Ritchie</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>
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        </sellerDetails>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <saleDate>10/04/2023</saleDate>
        <amountOfSecuritiesSold>208</amountOfSecuritiesSold>
        <grossProceeds>116.48</grossProceeds>
      </securitiesSoldInPast3Months>
      <noticeSignature>
        <noticeDate>10/12/2023</noticeDate>
        <signature>/s/ Ryan Riviere, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Garth Ritchie</signature>
      </noticeSignature>
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text: 144
  0001840684
  XXXXXXXX
  LIVE
  0001859690
  Arqit Quantum Inc.
  001-40777
  NOVA NORTH
  7 FLOOR, 11 BRESSENDEN PLACE
  LONDON
  X0
  SW1E 5BY
  44 203 91 70155
  Ritchie Garth
  Director
  Common
  Fidelity Brokerage Services LLC
  900 Salem Street
  Smithfield
  RI
  02917
  221
  123.63
  121926166
  10/12/2023
  NASDAQ
  Common
  10/02/2023
  Restricted Stock Vesting
  Issuer
  N
  221
  10/02/2023
  Compensation
  N
  Garth Ritchie
  Nova North 7 Floor 11 Bressenden Place
  London
  X0
  SW1E 5BY
  Common
  10/04/2023
  208
  116.48
  10/12/2023
  /s/ Ryan Riviere, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Garth Ritchie