<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019e3ca8-4668-7ea9-a30f-6ffd62258f60,g:41d1fbfb-b7bd-4dd2-8628-8999a857fa85-->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:ebc="http://www.easternbank.com/20260623" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:dtr-types="http://www.xbrl.org/dtr/type/2024-01-31" attributeFormDefault="unqualified" elementFormDefault="qualified" targetNamespace="http://www.easternbank.com/20260623">
  <xs:import namespace="http://fasb.org/srt/2026" schemaLocation="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd"/>
  <xs:import namespace="http://fasb.org/us-gaap-ebp/2026" schemaLocation="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd"/>
  <xs:import namespace="http://fasb.org/us-gaap/2026" schemaLocation="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd"/>
  <xs:import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd"/>
  <xs:import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd"/>
  <xs:import namespace="http://www.xbrl.org/dtr/type/2024-01-31" schemaLocation="https://www.xbrl.org/dtr/type/2024-01-31/types.xsd"/>
  <xs:import namespace="http://xbrl.sec.gov/dei/2026" schemaLocation="https://xbrl.sec.gov/dei/2026/dei-2026.xsd"/>
  <xs:annotation>
    <xs:appinfo>
      <link:linkbaseRef xmlns:xlink="http://www.w3.org/1999/xlink" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="ebc-20260623_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:type="simple"/>
      <link:linkbaseRef xmlns:xlink="http://www.w3.org/1999/xlink" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="ebc-20260623_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:type="simple"/>
      <link:linkbaseRef xmlns:xlink="http://www.w3.org/1999/xlink" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="ebc-20260623_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:type="simple"/>
      <link:linkbaseRef xmlns:xlink="http://www.w3.org/1999/xlink" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="ebc-20260623_cal.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:type="simple"/>
      <link:roleType id="Cover" roleURI="http://www.easternbank.com/role/Cover">
        <link:definition>0000001 - Document - Cover</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StatementsofNetAssetsAvailableforBenefits" roleURI="http://www.easternbank.com/role/StatementsofNetAssetsAvailableforBenefits">
        <link:definition>0000002 - Statement - Statements of Net Assets Available for Benefits</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StatementofChangesinNetAssetsAvailableforBenefits" roleURI="http://www.easternbank.com/role/StatementofChangesinNetAssetsAvailableforBenefits">
        <link:definition>0000003 - Statement - Statement of Changes in Net Assets Available for Benefits</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DESCRIPTIONOFTHEPLAN" roleURI="http://www.easternbank.com/role/DESCRIPTIONOFTHEPLAN">
        <link:definition>0000004 - Disclosure - DESCRIPTION OF THE PLAN</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIES" roleURI="http://www.easternbank.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIES">
        <link:definition>0000005 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FAIRVALUEMEASUREMENTS" roleURI="http://www.easternbank.com/role/FAIRVALUEMEASUREMENTS">
        <link:definition>0000006 - Disclosure - FAIR VALUE MEASUREMENTS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="TAXSTATUS" roleURI="http://www.easternbank.com/role/TAXSTATUS">
        <link:definition>0000007 - Disclosure - TAX STATUS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RISKSANDUNCERTAINTIES" roleURI="http://www.easternbank.com/role/RISKSANDUNCERTAINTIES">
        <link:definition>0000008 - Disclosure - RISKS AND UNCERTAINTIES</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RELATEDPARTYANDPARTYININTERESTTRANSACTIONS" roleURI="http://www.easternbank.com/role/RELATEDPARTYANDPARTYININTERESTTRANSACTIONS">
        <link:definition>0000009 - Disclosure - RELATED-PARTY AND PARTY-IN-INTEREST TRANSACTIONS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PLANTERMINATION" roleURI="http://www.easternbank.com/role/PLANTERMINATION">
        <link:definition>0000010 - Disclosure - PLAN TERMINATION</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ScheduleHLine4iScheduleofAssetsHeldAtEndofYear" roleURI="http://www.easternbank.com/role/ScheduleHLine4iScheduleofAssetsHeldAtEndofYear">
        <link:definition>0000011 - Disclosure - Schedule H, Line 4i &#8211; Schedule of Assets (Held At End of Year)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESPolicies" roleURI="http://www.easternbank.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESPolicies">
        <link:definition>0000012 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FAIRVALUEMEASUREMENTSTables" roleURI="http://www.easternbank.com/role/FAIRVALUEMEASUREMENTSTables">
        <link:definition>0000013 - Disclosure - FAIR VALUE MEASUREMENTS (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DESCRIPTIONOFTHEPLANDetails" roleURI="http://www.easternbank.com/role/DESCRIPTIONOFTHEPLANDetails">
        <link:definition>0000014 - Disclosure - DESCRIPTION OF THE PLAN (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FAIRVALUEMEASUREMENTSDetails" roleURI="http://www.easternbank.com/role/FAIRVALUEMEASUREMENTSDetails">
        <link:definition>0000015 - Disclosure - FAIR VALUE MEASUREMENTS (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RELATEDPARTYANDPARTYININTERESTTRANSACTIONSDetails" roleURI="http://www.easternbank.com/role/RELATEDPARTYANDPARTYININTERESTTRANSACTIONSDetails">
        <link:definition>0000016 - Disclosure - RELATED-PARTY AND PARTY-IN-INTEREST TRANSACTIONS (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ScheduleHLine4iScheduleofAssetsHeldAtEndofYearDetails" roleURI="http://www.easternbank.com/role/ScheduleHLine4iScheduleofAssetsHeldAtEndofYearDetails">
        <link:definition>0000017 - Disclosure - Schedule H, Line 4i &#8211; Schedule of Assets (Held At End of Year) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ScheduleHLine4iScheduleofAssetsHeldAtEndofYearDetails_1" roleURI="http://www.easternbank.com/role/ScheduleHLine4iScheduleofAssetsHeldAtEndofYearDetails_1">
        <link:definition>0000017 - Disclosure - Schedule H, Line 4i &#8211; Schedule of Assets (Held At End of Year) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
    </xs:appinfo>
  </xs:annotation>
  <xs:element id="ebc_EBP002Member" abstract="true" name="EBP002Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ebc_EBPRequisiteAgeForParticipation" abstract="false" name="EBPRequisiteAgeForParticipation" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ebc_EBPRequisiteServicePeriodForParticipation" abstract="false" name="EBPRequisiteServicePeriodForParticipation" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ebc_EBPRequisiteServicePeriodForSafeHarborNonelectiveContributions" abstract="false" name="EBPRequisiteServicePeriodForSafeHarborNonelectiveContributions" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ebc_EBPRequisiteAgeForSafeHarborNonelectiveContributions" abstract="false" name="EBPRequisiteAgeForSafeHarborNonelectiveContributions" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ebc_EBPFullTimeEmployeeHoursThreshold" abstract="false" name="EBPFullTimeEmployeeHoursThreshold" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ebc_EBPEligibilityServicePeriod" abstract="false" name="EBPEligibilityServicePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ebc_EBPEligibilityServicePeriodHoursThreshold" abstract="false" name="EBPEligibilityServicePeriodHoursThreshold" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ebc_EBPParticipantContributionMinimumAnnualCompensationToTotalCompensationPercentage" abstract="false" name="EBPParticipantContributionMinimumAnnualCompensationToTotalCompensationPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="ebc_EBPParticipantContributionMaximumAnnualCompensationToTotalCompensationPercentage" abstract="false" name="EBPParticipantContributionMaximumAnnualCompensationToTotalCompensationPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="ebc_EBPParticipantContributionAutomaticDeferralRefundPeriod" abstract="false" name="EBPParticipantContributionAutomaticDeferralRefundPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ebc_EBPNoteReceivableFromParticipantGeneralLoanMaximumBorrowingTerm" abstract="false" name="EBPNoteReceivableFromParticipantGeneralLoanMaximumBorrowingTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ebc_EBPNoteReceivableFromParticipantAccountPrimaryResidenceMaximumBorrowingTerm" abstract="false" name="EBPNoteReceivableFromParticipantAccountPrimaryResidenceMaximumBorrowingTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ebc_EBPParticipantLoanMaximumNumberOfLoansOutstandingPerParticipant" abstract="false" name="EBPParticipantLoanMaximumNumberOfLoansOutstandingPerParticipant" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ebc_EBPParticipantLoanBasisSpreadOnVariableRate" abstract="false" name="EBPParticipantLoanBasisSpreadOnVariableRate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
</xs:schema>
