<?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>0001589791</cik>
          <ccc>XXXXXXXX</ccc>
        </filerCredentials>
      </filer>
      <liveTestFlag>LIVE</liveTestFlag>



    </filerInfo>
  </headerData>
  <formData>
    <issuerInfo>
      <issuerCik>0000031462</issuerCik>
      <issuerName>ECOLAB INC.</issuerName>
      <secFileNumber>001-09328</secFileNumber>
      <issuerAddress>
        <com:street1>1 ECOLAB PLACE</com:street1>
        <com:city>SAINT PAUL</com:city>
        <com:stateOrCountry>MN</com:stateOrCountry>
        <com:zipCode>55102</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>18002326522</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Vautrinot Suzanne M</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Director</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <securitiesInformation>
      <securitiesClassTitle>common</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Wells Fargo Clearing Services</name>
        <address>
          <com:street1>1 North Jefferson Avenue</com:street1>
          <com:city>St. Louis</com:city>
          <com:stateOrCountry>MO</com:stateOrCountry>
          <com:zipCode>63103</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>1354</noOfUnitsSold>
      <aggregateMarketValue>383394.79</aggregateMarketValue>
      <noOfUnitsOutstanding>283624912</noOfUnitsOutstanding>
      <approxSaleDate>08/19/2025</approxSaleDate>
      <securitiesExchangeName>NYSE</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>common</securitiesClassTitle>
      <acquiredDate>08/14/2025</acquiredDate>
      <natureOfAcquisitionTransaction>Stock Options</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>1354</amountOfSecuritiesAcquired>
      <paymentDate>08/14/2025</paymentDate>
      <natureOfPayment>check</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <remarks>shares sold today in account for William C Keller Revocable Trust, Suzanne M Vautrinot, trustee</remarks>
    <noticeSignature>
      <noticeDate>08/19/2025</noticeDate>
      <signature>Suzanne M Vautrinot</signature>
    </noticeSignature>
  </formData>
</edgarSubmission>
