<?xml version="1.0" encoding="UTF-8"?>
<edgarSubmission xmlns="http://www.sec.gov/edgar/ta/tatwofiler">
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    <submissionType>TA-2</submissionType>
    <filerInfo>
      <periodOfReport>2018-12-31</periodOfReport>
      <filer>
        <fileNumber>084-06072</fileNumber>
        <filerCredentials>
          <cik>0001227021</cik>
          <ccc>XXXXXXXX</ccc>
        </filerCredentials>
      </filer>
      <testOrLive>LIVE</testOrLive>
      <flags>
        <returnCopy>true</returnCopy>
        <isFilingAmendment>false</isFilingAmendment>
      </flags>
      <entityName>BROWN BROTHERS HARRIMAN &amp; CO</entityName>
    </filerInfo>
  </headerData>
  <formData>
    <engagedServiceCompany>
      <serviceCompany>None</serviceCompany>
      <registrantEngagedService>N</registrantEngagedService>
    </engagedServiceCompany>
    <registrantRegulatoryAgency>
      <regulatoryAgency>Securities and Exchange Commission</regulatoryAgency>
      <amendmentFiled>Yes, filed amendment(s)</amendmentFiled>
    </registrantRegulatoryAgency>
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      <numberMasterSecurityHolderFilings>14614</numberMasterSecurityHolderFilings>
      <numberIndividualAccounts>14614</numberIndividualAccounts>
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      <numberDirectRegistSystemAccounts>1763</numberDirectRegistSystemAccounts>
      <securityHolderAccounts>
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        <debtSecurity>0.00</debtSecurity>
        <openEndInvestmentCompany>0.00</openEndInvestmentCompany>
        <limitedPartnership>11.00</limitedPartnership>
        <municipalDebt>0.00</municipalDebt>
        <other>28.00</other>
      </securityHolderAccounts>
      <securityHolderData>
        <transMaintainMasterSecHolder>
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          <municipalDebt>0</municipalDebt>
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        </transMaintainMasterSecHolder>
        <transNotMaintMasterSecHolder>
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        </transNotMaintMasterSecHolder>
        <notTransMaintMasterSecHolder>
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          <debtSecurity>0</debtSecurity>
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          <municipalDebt>0</municipalDebt>
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        </notTransMaintMasterSecHolder>
        <dividendReinvDirectPurchasePlan>491</dividendReinvDirectPurchasePlan>
        <directRegistrationSystem>169</directRegistrationSystem>
        <dividendAndInterest>
          <numberIssues>17898</numberIssues>
          <amountIssues>11738634413.43</amountIssues>
        </dividendAndInterest>
        <priorAgent>
          <numberIssues>0</numberIssues>
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        </priorAgent>
        <currentAgent>
          <numberIssues>0</numberIssues>
          <amountIssues>0.00</amountIssues>
        </currentAgent>
        <numberFiled>0</numberFiled>
        <alwaysCompliant>Yes</alwaysCompliant>
        <total>8661</total>
        <totalOtherThanReceiptOrderDate>421</totalOtherThanReceiptOrderDate>
      </securityHolderData>
      <databaseSearches>
        <databaseSearchDate>03/29/2019</databaseSearchDate>
        <numberLostAccountsSearched>0</numberLostAccountsSearched>
        <numberAddressesFromSearch>0</numberAddressesFromSearch>
      </databaseSearches>
      <numberLostAccountsRemittedToStates>0</numberLostAccountsRemittedToStates>
    </serviceCompanyData>
    <signatureData>
      <signatureName>Ursula Costigan</signatureName>
      <signaturePhoneNumber>(617) 772-6161</signaturePhoneNumber>
      <signatureTitle>Vice President</signatureTitle>
      <signatureDate>03/29/2019</signatureDate>
    </signatureData>
  </formData>
</edgarSubmission>
