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>0001293167</cik>
            <ccc>XXXXXXXX</ccc>
          </filerCredentials>
        </filer>
        <liveTestFlag>LIVE</liveTestFlag>
  
  
  
      </filerInfo>
    </headerData>
    <formData>
      <issuerInfo>
        <issuerCik>0001722482</issuerCik>
        <issuerName>Avantor, Inc.</issuerName>
        <secFileNumber>001-38912</secFileNumber>
        <issuerAddress>
          <com:street1>RADNOR CORPORATE CENTER, BUILDING ONE</com:street1>
          <com:street2>SUITE 200, 100 MATSONFORD ROAD</com:street2>
          <com:city>RADNOR</com:city>
          <com:stateOrCountry>PA</com:stateOrCountry>
          <com:zipCode>19087</com:zipCode>
        </issuerAddress>
        <issuerContactPhone>(610) 386-1700</issuerContactPhone>
        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Szlosek Thomas A</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>Former officer</relationshipToIssuer>
        </relationshipsToIssuer>
      </issuerInfo>
      <securitiesInformation>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <brokerOrMarketmakerDetails>
          <name>Merrill</name>
          <address>
            <com:street1>8890 Lyra Dr 5th Flr</com:street1>
            <com:city>Columbus</com:city>
            <com:stateOrCountry>OH</com:stateOrCountry>
            <com:zipCode>43240</com:zipCode>
          </address>
        </brokerOrMarketmakerDetails>
        <noOfUnitsSold>82117</noOfUnitsSold>
        <aggregateMarketValue>1744466.00</aggregateMarketValue>
        <noOfUnitsOutstanding>675918430</noOfUnitsOutstanding>
        <approxSaleDate>10/12/2023</approxSaleDate>
        <securitiesExchangeName>NYSE</securitiesExchangeName>
      </securitiesInformation>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>02/20/2020</acquiredDate>
        <natureOfAcquisitionTransaction>Stock option exercise</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Avantor Inc</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>82117</amountOfSecuritiesAcquired>
        <paymentDate>10/12/2023</paymentDate>
        <natureOfPayment>Cash</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
      <securitiesSoldInPast3Months>
        <sellerDetails>
          <name>Thomas Szlosek</name>
          <address>
            <com:street1>Building One, Suite 200</com:street1>
            <com:street2>100 Matsonford Road</com:street2>
            <com:city>Radnor</com:city>
            <com:stateOrCountry>PA</com:stateOrCountry>
            <com:zipCode>19087</com:zipCode>
          </address>
        </sellerDetails>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <saleDate>09/12/2023</saleDate>
        <amountOfSecuritiesSold>110000</amountOfSecuritiesSold>
        <grossProceeds>2349596.00</grossProceeds>
      </securitiesSoldInPast3Months>
      <securitiesSoldInPast3Months>
        <sellerDetails>
          <name>Thomas Szlosek</name>
          <address>
            <com:street1>Building One Suite 200 100 Matsonford Rd</com:street1>
            <com:city>Radnor</com:city>
            <com:stateOrCountry>PA</com:stateOrCountry>
            <com:zipCode>19087</com:zipCode>
          </address>
        </sellerDetails>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <saleDate>09/20/2023</saleDate>
        <amountOfSecuritiesSold>75000</amountOfSecuritiesSold>
        <grossProceeds>1682800.00</grossProceeds>
      </securitiesSoldInPast3Months>
      <noticeSignature>
        <noticeDate>10/12/2023</noticeDate>
        <signature>Thomas Szlosek</signature>
      </noticeSignature>
    </formData>
  </edgarSubmission>
metadata_documents: [{"type": "144", "sequence": "1", "filename": "primary_doc.xml", "secsgml_size_bytes": 4028}]
text: 144
  0001293167
  XXXXXXXX
  LIVE
  0001722482
  Avantor, Inc.
  001-38912
  RADNOR CORPORATE CENTER, BUILDING ONE
  SUITE 200, 100 MATSONFORD ROAD
  RADNOR
  PA
  19087
  (610) 386-1700
  Szlosek Thomas A
  Former officer
  Common
  Merrill
  8890 Lyra Dr 5th Flr
  Columbus
  OH
  43240
  82117
  1744466.00
  675918430
  10/12/2023
  NYSE
  Common
  02/20/2020
  Stock option exercise
  Avantor Inc
  N
  82117
  10/12/2023
  Cash
  N
  Thomas Szlosek
  Building One, Suite 200
  100 Matsonford Road
  Radnor
  PA
  19087
  Common
  09/12/2023
  110000
  2349596.00
  Thomas Szlosek
  Building One Suite 200 100 Matsonford Rd
  Radnor
  PA
  19087
  Common
  09/20/2023
  75000
  1682800.00
  10/12/2023
  Thomas Szlosek