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>0001967066</cik>
            <ccc>XXXXXXXX</ccc>
          </filerCredentials>
        </filer>
        <liveTestFlag>LIVE</liveTestFlag>
  
  
  
      </filerInfo>
    </headerData>
    <formData>
      <issuerInfo>
        <issuerCik>0001859690</issuerCik>
        <issuerName>Arqit Quantum Inc.</issuerName>
        <secFileNumber>001-40777</secFileNumber>
        <issuerAddress>
          <com:street1>3 ORCHARD PLACE</com:street1>
          <com:city>LONDON</com:city>
          <com:stateOrCountry>X0</com:stateOrCountry>
          <com:zipCode>SW1H 0BF</com:zipCode>
        </issuerAddress>
        <issuerContactPhone>44 203 91 70155</issuerContactPhone>
        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Shiu Daniel</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>Officer</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>6500</noOfUnitsSold>
        <aggregateMarketValue>247182.70</aggregateMarketValue>
        <noOfUnitsOutstanding>11545354</noOfUnitsOutstanding>
        <approxSaleDate>06/23/2025</approxSaleDate>
        <securitiesExchangeName>NASDAQ</securitiesExchangeName>
      </securitiesInformation>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>09/30/2022</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>7</amountOfSecuritiesAcquired>
        <paymentDate>09/30/2022</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>10/03/2022</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>10</amountOfSecuritiesAcquired>
        <paymentDate>10/03/2022</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>10/04/2022</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>8</amountOfSecuritiesAcquired>
        <paymentDate>10/04/2022</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>10/05/2022</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>9</amountOfSecuritiesAcquired>
        <paymentDate>10/05/2022</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>10/06/2022</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>9</amountOfSecuritiesAcquired>
        <paymentDate>10/06/2022</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>10/07/2022</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>9</amountOfSecuritiesAcquired>
        <paymentDate>10/07/2022</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>01/03/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>8</amountOfSecuritiesAcquired>
        <paymentDate>01/03/2023</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>01/04/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>7</amountOfSecuritiesAcquired>
        <paymentDate>01/04/2023</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>01/05/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>8</amountOfSecuritiesAcquired>
        <paymentDate>01/05/2023</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>01/06/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>8</amountOfSecuritiesAcquired>
        <paymentDate>01/06/2023</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>01/09/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>8</amountOfSecuritiesAcquired>
        <paymentDate>01/09/2023</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>01/10/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>8</amountOfSecuritiesAcquired>
        <paymentDate>01/10/2023</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>01/11/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>8</amountOfSecuritiesAcquired>
        <paymentDate>01/11/2023</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>04/01/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>53</amountOfSecuritiesAcquired>
        <paymentDate>04/01/2023</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>07/01/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>58</amountOfSecuritiesAcquired>
        <paymentDate>07/01/2023</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>10/01/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>189</amountOfSecuritiesAcquired>
        <paymentDate>10/01/2023</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>01/02/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>190</amountOfSecuritiesAcquired>
        <paymentDate>01/02/2024</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>03/26/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Stock Option Exercise</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>2329</amountOfSecuritiesAcquired>
        <paymentDate>03/26/2024</paymentDate>
        <natureOfPayment>Cash</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>04/01/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>190</amountOfSecuritiesAcquired>
        <paymentDate>04/01/2024</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>07/01/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>190</amountOfSecuritiesAcquired>
        <paymentDate>07/01/2024</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>07/31/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Stock Option Exercise</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>717</amountOfSecuritiesAcquired>
        <paymentDate>07/31/2024</paymentDate>
        <natureOfPayment>Cash</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>10/01/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>331</amountOfSecuritiesAcquired>
        <paymentDate>10/01/2024</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>01/01/2025</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>223</amountOfSecuritiesAcquired>
        <paymentDate>01/01/2025</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>01/28/2025</acquiredDate>
        <natureOfAcquisitionTransaction>Stock Option Exercise</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>859</amountOfSecuritiesAcquired>
        <paymentDate>01/28/2025</paymentDate>
        <natureOfPayment>Cash</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>04/01/2025</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>458</amountOfSecuritiesAcquired>
        <paymentDate>04/01/2025</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>05/07/2025</acquiredDate>
        <natureOfAcquisitionTransaction>Stock Option Exercise</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>606</amountOfSecuritiesAcquired>
        <paymentDate>05/07/2025</paymentDate>
        <natureOfPayment>Cash</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
      <securitiesSoldInPast3Months>
        <sellerDetails>
          <name>Daniel Shiu</name>
          <address>
            <com:street1>3 Orchard Place</com:street1>
            <com:city>London</com:city>
            <com:stateOrCountry>X0</com:stateOrCountry>
            <com:zipCode>SW1H 0BF</com:zipCode>
          </address>
        </sellerDetails>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <saleDate>04/02/2025</saleDate>
        <amountOfSecuritiesSold>230</amountOfSecuritiesSold>
        <grossProceeds>3175.91</grossProceeds>
      </securitiesSoldInPast3Months>
      <noticeSignature>
        <noticeDate>06/23/2025</noticeDate>
        <signature>/s/ Daniel Tucci, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Daniel Shiu</signature>
      </noticeSignature>
    </formData>
  </edgarSubmission>
metadata_documents: [{"type": "144", "sequence": "1", "filename": "primary_doc.xml", "secsgml_size_bytes": 16752}]
text: 144
  0001967066
  XXXXXXXX
  LIVE
  0001859690
  Arqit Quantum Inc.
  001-40777
  3 ORCHARD PLACE
  LONDON
  X0
  SW1H 0BF
  44 203 91 70155
  Shiu Daniel
  Officer
  Common
  Fidelity Brokerage Services LLC
  900 Salem Street
  Smithfield
  RI
  02917
  6500
  247182.70
  11545354
  06/23/2025
  NASDAQ
  Common
  09/30/2022
  Restricted Stock Vesting
  Issuer
  N
  7
  09/30/2022
  Compensation
  Common
  10/03/2022
  Restricted Stock Vesting
  Issuer
  N
  10
  10/03/2022
  Compensation
  Common
  10/04/2022
  Restricted Stock Vesting
  Issuer
  N
  8
  10/04/2022
  Compensation
  Common
  10/05/2022
  Restricted Stock Vesting
  Issuer
  N
  9
  10/05/2022
  Compensation
  Common
  10/06/2022
  Restricted Stock Vesting
  Issuer
  N
  9
  10/06/2022
  Compensation
  Common
  10/07/2022
  Restricted Stock Vesting
  Issuer
  N
  9
  10/07/2022
  Compensation
  Common
  01/03/2023
  Restricted Stock Vesting
  Issuer
  N
  8
  01/03/2023
  Compensation
  Common
  01/04/2023
  Restricted Stock Vesting
  Issuer
  N
  7
  01/04/2023
  Compensation
  Common
  01/05/2023
  Restricted Stock Vesting
  Issuer
  N
  8
  01/05/2023
  Compensation
  Common
  01/06/2023
  Restricted Stock Vesting
  Issuer
  N
  8
  01/06/2023
  Compensation
  Common
  01/09/2023
  Restricted Stock Vesting
  Issuer
  N
  8
  01/09/2023
  Compensation
  Common
  01/10/2023
  Restricted Stock Vesting
  Issuer
  N
  8
  01/10/2023
  Compensation
  Common
  01/11/2023
  Restricted Stock Vesting
  Issuer
  N
  8
  01/11/2023
  Compensation
  Common
  04/01/2023
  Restricted Stock Vesting
  Issuer
  N
  53
  04/01/2023
  Compensation
  Common
  07/01/2023
  Restricted Stock Vesting
  Issuer
  N
  58
  07/01/2023
  Compensation
  Common
  10/01/2023
  Restricted Stock Vesting
  Issuer
  N
  189
  10/01/2023
  Compensation
  Common
  01/02/2024
  Restricted Stock Vesting
  Issuer
  N
  190
  01/02/2024
  Compensation
  Common
  03/26/2024
  Stock Option Exercise
  Issuer
  N
  2329
  03/26/2024
  Cash
  Common
  04/01/2024
  Restricted Stock Vesting
  Issuer
  N
  190
  04/01/2024
  Compensation
  Common
  07/01/2024
  Restricted Stock Vesting
  Issuer
  N
  190
  07/01/2024
  Compensation
  Common
  07/31/2024
  Stock Option Exercise
  Issuer
  N
  717
  07/31/2024
  Cash
  Common
  10/01/2024
  Restricted Stock Vesting
  Issuer
  N
  331
  10/01/2024
  Compensation
  Common
  01/01/2025
  Restricted Stock Vesting
  Issuer
  N
  223
  01/01/2025
  Compensation
  Common
  01/28/2025
  Stock Option Exercise
  Issuer
  N
  859
  01/28/2025
  Cash
  Common
  04/01/2025
  Restricted Stock Vesting
  Issuer
  N
  458
  04/01/2025
  Compensation
  Common
  05/07/2025
  Stock Option Exercise
  Issuer
  N
  606
  05/07/2025
  Cash
  N
  Daniel Shiu
  3 Orchard Place
  London
  X0
  SW1H 0BF
  Common
  04/02/2025
  230
  3175.91
  06/23/2025
  /s/ Daniel Tucci, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Daniel Shiu