<?xml version="1.0" encoding="utf-8"?>
<!--XBRL document created with Toppan Merrill Bridge  11.3.0.1 -->
<!--Based on XBRL 2.1-->
<!--Created on: 6/23/2026 7:14:02 PM-->
<!--Modified on: 6/23/2026 7:14:02 PM-->
<link:linkbase xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt">
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DocumentDocumentAndEntityInformation" roleURI="http://www.ameriserv.com/role/DocumentDocumentAndEntityInformation" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#StatementStatementsOfNetAssetsAvailableForBenefits" roleURI="http://www.ameriserv.com/role/StatementStatementsOfNetAssetsAvailableForBenefits" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#StatementStatementsOfChangesInNetAssetsAvailableForBenefits" roleURI="http://www.ameriserv.com/role/StatementStatementsOfChangesInNetAssetsAvailableForBenefits" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureDescriptionOfPlan" roleURI="http://www.ameriserv.com/role/DisclosureDescriptionOfPlan" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureSummaryOfSignificantAccountingPolicies" roleURI="http://www.ameriserv.com/role/DisclosureSummaryOfSignificantAccountingPolicies" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosurePlanTermination" roleURI="http://www.ameriserv.com/role/DisclosurePlanTermination" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureTaxStatus" roleURI="http://www.ameriserv.com/role/DisclosureTaxStatus" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosurePartyInInterestTransactions" roleURI="http://www.ameriserv.com/role/DisclosurePartyInInterestTransactions" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureFairValueMeasurements" roleURI="http://www.ameriserv.com/role/DisclosureFairValueMeasurements" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureFairValueOfFinancialInstruments" roleURI="http://www.ameriserv.com/role/DisclosureFairValueOfFinancialInstruments" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureFullyBenefitResponsiveInvestmentContract" roleURI="http://www.ameriserv.com/role/DisclosureFullyBenefitResponsiveInvestmentContract" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureRiskAndUncertainties" roleURI="http://www.ameriserv.com/role/DisclosureRiskAndUncertainties" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureScheduleHLine4iScheduleOfAssetsHeldAtEndOfYear" roleURI="http://www.ameriserv.com/role/DisclosureScheduleHLine4iScheduleOfAssetsHeldAtEndOfYear" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureSummaryOfSignificantAccountingPoliciesPolicies" roleURI="http://www.ameriserv.com/role/DisclosureSummaryOfSignificantAccountingPoliciesPolicies" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureFairValueMeasurementsTables" roleURI="http://www.ameriserv.com/role/DisclosureFairValueMeasurementsTables" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureDescriptionOfPlanDetails" roleURI="http://www.ameriserv.com/role/DisclosureDescriptionOfPlanDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureDescriptionOfPlanContributionsDetails" roleURI="http://www.ameriserv.com/role/DisclosureDescriptionOfPlanContributionsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureDescriptionOfPlanVestingDetails" roleURI="http://www.ameriserv.com/role/DisclosureDescriptionOfPlanVestingDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureDescriptionOfPlanNotesReceivableFromParticipantsDetails" roleURI="http://www.ameriserv.com/role/DisclosureDescriptionOfPlanNotesReceivableFromParticipantsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureDescriptionOfPlanPaymentOfBenefitsAndForfeituresDetails" roleURI="http://www.ameriserv.com/role/DisclosureDescriptionOfPlanPaymentOfBenefitsAndForfeituresDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureSummaryOfSignificantAccountingPoliciesDetails" roleURI="http://www.ameriserv.com/role/DisclosureSummaryOfSignificantAccountingPoliciesDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosurePlanTerminationDetails" roleURI="http://www.ameriserv.com/role/DisclosurePlanTerminationDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureTaxStatusDetails" roleURI="http://www.ameriserv.com/role/DisclosureTaxStatusDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosurePartyInInterestTransactionsDetails" roleURI="http://www.ameriserv.com/role/DisclosurePartyInInterestTransactionsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureFairValueMeasurementsDetails" roleURI="http://www.ameriserv.com/role/DisclosureFairValueMeasurementsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureFairValueMeasurementsNarrativeDetails" roleURI="http://www.ameriserv.com/role/DisclosureFairValueMeasurementsNarrativeDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureRiskAndUncertaintiesDetails" roleURI="http://www.ameriserv.com/role/DisclosureRiskAndUncertaintiesDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureScheduleHLine4iScheduleOfAssetsHeldAtEndOfYearDetails" roleURI="http://www.ameriserv.com/role/DisclosureScheduleHLine4iScheduleOfAssetsHeldAtEndOfYearDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="asrv-20251231.xsd#DisclosureScheduleHLine4iScheduleOfAssetsHeldAtEndOfYearDefaultDetails" roleURI="http://www.ameriserv.com/role/DisclosureScheduleHLine4iScheduleOfAssetsHeldAtEndOfYearDefaultDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <link:roleRef roleURI="http://fasb.org/srt/role/srt-eedm/ExtensibleEnumerationLists" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-roles-2026.xsd#eedm1" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ameriserv.com/role/DisclosureStandardAndCustomAxisDomainDefaults" xlink:href="asrv-20251231.xsd#DisclosureStandardAndCustomAxisDomainDefaults" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" />
  <link:arcroleRef arcroleURI="http://www.esma.europa.eu/xbrl/esef/arcrole/wider-narrower" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/arcrole/esma-arcrole-2018-11-21.xsd#wider-narrower" />
  <link:definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureStandardAndCustomAxisDomainDefaults" xlink:type="extended" xlink:title="99900 - Disclosure - Standard And Custom Axis Domain Defaults">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis_1" xlink:title="dei_LegalEntityAxis_1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain_1" xlink:title="dei_EntityDomain_1" />
    <link:definitionArc xlink:type="arc" xlink:from="dei_LegalEntityAxis_1" xlink:to="dei_EntityDomain_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:title="definition:dei_LegalEntityAxis_1 To dei_EntityDomain_1" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis" xlink:label="us-gaap_InvestmentTypeAxis_1" xlink:title="us-gaap_InvestmentTypeAxis_1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="us-gaap_InvestmentTypeCategorizationMember_1" xlink:title="us-gaap_InvestmentTypeCategorizationMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentTypeAxis_1" xlink:to="us-gaap_InvestmentTypeCategorizationMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:title="definition:us-gaap_InvestmentTypeAxis_1 To us-gaap_InvestmentTypeCategorizationMember_1" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameAxis" xlink:label="us-gaap_InvestmentIssuerNameAxis_1" xlink:title="us-gaap_InvestmentIssuerNameAxis_1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_1" xlink:title="us-gaap_InvestmentIssuerNameDomain_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameAxis_1" xlink:to="us-gaap_InvestmentIssuerNameDomain_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:title="definition:us-gaap_InvestmentIssuerNameAxis_1 To us-gaap_InvestmentIssuerNameDomain_1" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis" xlink:label="srt_RangeAxis_1" xlink:title="srt_RangeAxis_1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember" xlink:label="srt_RangeMember_1" xlink:title="srt_RangeMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="srt_RangeAxis_1" xlink:to="srt_RangeMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:title="definition:srt_RangeAxis_1 To srt_RangeMember_1" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestAxis" xlink:label="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestAxis_1" xlink:title="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestAxis_1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestDomain" xlink:label="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestDomain_1" xlink:title="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestDomain_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestAxis_1" xlink:to="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestDomain_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:title="definition:us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestAxis_1 To us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestDomain_1" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_1" xlink:title="us-gaap_FairValueByFairValueHierarchyLevelAxis_1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_1" xlink:title="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_FairValueByFairValueHierarchyLevelAxis_1" xlink:to="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:title="definition:us-gaap_FairValueByFairValueHierarchyLevelAxis_1 To us-gaap_FairValueMeasurementsFairValueHierarchyDomain_1" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StatementScenarioAxis" xlink:label="srt_StatementScenarioAxis_1" xlink:title="srt_StatementScenarioAxis_1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScenarioUnspecifiedDomain" xlink:label="srt_ScenarioUnspecifiedDomain_1" xlink:title="srt_ScenarioUnspecifiedDomain_1" />
    <link:definitionArc xlink:type="arc" xlink:from="srt_StatementScenarioAxis_1" xlink:to="srt_ScenarioUnspecifiedDomain_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:title="definition:srt_StatementScenarioAxis_1 To srt_ScenarioUnspecifiedDomain_1" order="1" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://fasb.org/srt/role/srt-eedm/ExtensibleEnumerationLists" xlink:type="extended" xlink:title="SRT Extensible Enumeration Domain Members">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_3" xlink:title="us-gaap_InvestmentIssuerNameDomain_3" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_AmeriservFinancialInc.Member" xlink:label="asrv_AmeriservFinancialInc.Member_1" xlink:title="asrv_AmeriservFinancialInc.Member_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_3" xlink:to="asrv_AmeriservFinancialInc.Member_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_3 To asrv_AmeriservFinancialInc.Member_1" order="2" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_4" xlink:title="us-gaap_InvestmentIssuerNameDomain_4" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_BlackrockMember" xlink:label="asrv_BlackrockMember_1" xlink:title="asrv_BlackrockMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_4" xlink:to="asrv_BlackrockMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_4 To asrv_BlackrockMember_1" order="3" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_5" xlink:title="us-gaap_InvestmentIssuerNameDomain_5" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_CalvertMember" xlink:label="asrv_CalvertMember_1" xlink:title="asrv_CalvertMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_5" xlink:to="asrv_CalvertMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_5 To asrv_CalvertMember_1" order="4" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_6" xlink:title="us-gaap_InvestmentIssuerNameDomain_6" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_DodgeCoxMember" xlink:label="asrv_DodgeCoxMember_1" xlink:title="asrv_DodgeCoxMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_6" xlink:to="asrv_DodgeCoxMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_6 To asrv_DodgeCoxMember_1" order="5" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_7" xlink:title="us-gaap_InvestmentIssuerNameDomain_7" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_FederatedHermesMember" xlink:label="asrv_FederatedHermesMember_1" xlink:title="asrv_FederatedHermesMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_7" xlink:to="asrv_FederatedHermesMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_7 To asrv_FederatedHermesMember_1" order="6" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_8" xlink:title="us-gaap_InvestmentIssuerNameDomain_8" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_FidelityMember" xlink:label="asrv_FidelityMember_1" xlink:title="asrv_FidelityMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_8" xlink:to="asrv_FidelityMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_8 To asrv_FidelityMember_1" order="7" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_9" xlink:title="us-gaap_InvestmentIssuerNameDomain_9" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_JohnHancockIiiMember" xlink:label="asrv_JohnHancockIiiMember_1" xlink:title="asrv_JohnHancockIiiMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_9" xlink:to="asrv_JohnHancockIiiMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_9 To asrv_JohnHancockIiiMember_1" order="8" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_10" xlink:title="us-gaap_InvestmentIssuerNameDomain_10" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_LoomisSaylesMember" xlink:label="asrv_LoomisSaylesMember_1" xlink:title="asrv_LoomisSaylesMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_10" xlink:to="asrv_LoomisSaylesMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_10 To asrv_LoomisSaylesMember_1" order="9" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_11" xlink:title="us-gaap_InvestmentIssuerNameDomain_11" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_NatixisLoomisSaylesMember" xlink:label="asrv_NatixisLoomisSaylesMember_1" xlink:title="asrv_NatixisLoomisSaylesMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_11" xlink:to="asrv_NatixisLoomisSaylesMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_11 To asrv_NatixisLoomisSaylesMember_1" order="10" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_12" xlink:title="us-gaap_InvestmentIssuerNameDomain_12" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_NuveenMember" xlink:label="asrv_NuveenMember_1" xlink:title="asrv_NuveenMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_12" xlink:to="asrv_NuveenMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_12 To asrv_NuveenMember_1" order="11" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_13" xlink:title="us-gaap_InvestmentIssuerNameDomain_13" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_PimcoMember" xlink:label="asrv_PimcoMember_1" xlink:title="asrv_PimcoMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_13" xlink:to="asrv_PimcoMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_13 To asrv_PimcoMember_1" order="12" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_14" xlink:title="us-gaap_InvestmentIssuerNameDomain_14" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_PrimecapMember" xlink:label="asrv_PrimecapMember_1" xlink:title="asrv_PrimecapMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_14" xlink:to="asrv_PrimecapMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_14 To asrv_PrimecapMember_1" order="13" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_15" xlink:title="us-gaap_InvestmentIssuerNameDomain_15" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_T.RowePriceMember" xlink:label="asrv_T.RowePriceMember_1" xlink:title="asrv_T.RowePriceMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_15" xlink:to="asrv_T.RowePriceMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_15 To asrv_T.RowePriceMember_1" order="14" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_16" xlink:title="us-gaap_InvestmentIssuerNameDomain_16" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_VanguardMember" xlink:label="asrv_VanguardMember_1" xlink:title="asrv_VanguardMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_16" xlink:to="asrv_VanguardMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_16 To asrv_VanguardMember_1" order="15" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_17" xlink:title="us-gaap_InvestmentIssuerNameDomain_17" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_VirtusKarMember" xlink:label="asrv_VirtusKarMember_1" xlink:title="asrv_VirtusKarMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_17" xlink:to="asrv_VirtusKarMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_17 To asrv_VirtusKarMember_1" order="16" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_18" xlink:title="us-gaap_InvestmentIssuerNameDomain_18" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_PathroadConservativeFixedIncomeMember" xlink:label="asrv_PathroadConservativeFixedIncomeMember_1" xlink:title="asrv_PathroadConservativeFixedIncomeMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_18" xlink:to="asrv_PathroadConservativeFixedIncomeMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_18 To asrv_PathroadConservativeFixedIncomeMember_1" order="17" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_19" xlink:title="us-gaap_InvestmentIssuerNameDomain_19" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_PathroadStrategicBalancedGrowthIncomeMember" xlink:label="asrv_PathroadStrategicBalancedGrowthIncomeMember_1" xlink:title="asrv_PathroadStrategicBalancedGrowthIncomeMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_19" xlink:to="asrv_PathroadStrategicBalancedGrowthIncomeMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_19 To asrv_PathroadStrategicBalancedGrowthIncomeMember_1" order="18" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_20" xlink:title="us-gaap_InvestmentIssuerNameDomain_20" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_PathroadStrategicCapitalAppreciationIncomeMember" xlink:label="asrv_PathroadStrategicCapitalAppreciationIncomeMember_1" xlink:title="asrv_PathroadStrategicCapitalAppreciationIncomeMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_20" xlink:to="asrv_PathroadStrategicCapitalAppreciationIncomeMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_20 To asrv_PathroadStrategicCapitalAppreciationIncomeMember_1" order="19" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_21" xlink:title="us-gaap_InvestmentIssuerNameDomain_21" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_PathroadStrategicConservativeGrowthIncomeMember" xlink:label="asrv_PathroadStrategicConservativeGrowthIncomeMember_1" xlink:title="asrv_PathroadStrategicConservativeGrowthIncomeMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_21" xlink:to="asrv_PathroadStrategicConservativeGrowthIncomeMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_21 To asrv_PathroadStrategicConservativeGrowthIncomeMember_1" order="20" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_22" xlink:title="us-gaap_InvestmentIssuerNameDomain_22" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_PathroadStrategicLongTermEquityMember" xlink:label="asrv_PathroadStrategicLongTermEquityMember_1" xlink:title="asrv_PathroadStrategicLongTermEquityMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_22" xlink:to="asrv_PathroadStrategicLongTermEquityMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_22 To asrv_PathroadStrategicLongTermEquityMember_1" order="21" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_23" xlink:title="us-gaap_InvestmentIssuerNameDomain_23" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_PathroadTacticalBalancedGrowthIncomeMember" xlink:label="asrv_PathroadTacticalBalancedGrowthIncomeMember_2" xlink:title="asrv_PathroadTacticalBalancedGrowthIncomeMember_2" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_23" xlink:to="asrv_PathroadTacticalBalancedGrowthIncomeMember_2" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_23 To asrv_PathroadTacticalBalancedGrowthIncomeMember_2" order="22" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_24" xlink:title="us-gaap_InvestmentIssuerNameDomain_24" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_PathroadTacticalCapitalAppreciationIncomeMember" xlink:label="asrv_PathroadTacticalCapitalAppreciationIncomeMember_2" xlink:title="asrv_PathroadTacticalCapitalAppreciationIncomeMember_2" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_24" xlink:to="asrv_PathroadTacticalCapitalAppreciationIncomeMember_2" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_24 To asrv_PathroadTacticalCapitalAppreciationIncomeMember_2" order="23" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_25" xlink:title="us-gaap_InvestmentIssuerNameDomain_25" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_PathroadTacticalConservativeGrowthIncomeMember" xlink:label="asrv_PathroadTacticalConservativeGrowthIncomeMember_1" xlink:title="asrv_PathroadTacticalConservativeGrowthIncomeMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_25" xlink:to="asrv_PathroadTacticalConservativeGrowthIncomeMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_25 To asrv_PathroadTacticalConservativeGrowthIncomeMember_1" order="24" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_26" xlink:title="us-gaap_InvestmentIssuerNameDomain_26" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_PathroadTacticalIntermediateTermFixedIncomeMember" xlink:label="asrv_PathroadTacticalIntermediateTermFixedIncomeMember_1" xlink:title="asrv_PathroadTacticalIntermediateTermFixedIncomeMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_26" xlink:to="asrv_PathroadTacticalIntermediateTermFixedIncomeMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_26 To asrv_PathroadTacticalIntermediateTermFixedIncomeMember_1" order="25" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_27" xlink:title="us-gaap_InvestmentIssuerNameDomain_27" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_PathroadTacticalLongTermEquityMember" xlink:label="asrv_PathroadTacticalLongTermEquityMember_1" xlink:title="asrv_PathroadTacticalLongTermEquityMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_27" xlink:to="asrv_PathroadTacticalLongTermEquityMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_27 To asrv_PathroadTacticalLongTermEquityMember_1" order="26" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_28" xlink:title="us-gaap_InvestmentIssuerNameDomain_28" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_GoldmanSachsFinancialSquareGovTFundMember" xlink:label="asrv_GoldmanSachsFinancialSquareGovTFundMember_1" xlink:title="asrv_GoldmanSachsFinancialSquareGovTFundMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_28" xlink:to="asrv_GoldmanSachsFinancialSquareGovTFundMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_28 To asrv_GoldmanSachsFinancialSquareGovTFundMember_1" order="27" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_29" xlink:title="us-gaap_InvestmentIssuerNameDomain_29" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_GoldmanSachsFinancialTreasuryObligationsMember" xlink:label="asrv_GoldmanSachsFinancialTreasuryObligationsMember_1" xlink:title="asrv_GoldmanSachsFinancialTreasuryObligationsMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_29" xlink:to="asrv_GoldmanSachsFinancialTreasuryObligationsMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_29 To asrv_GoldmanSachsFinancialTreasuryObligationsMember_1" order="28" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain_30" xlink:title="us-gaap_InvestmentIssuerNameDomain_30" />
    <link:loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_AnnuityInsuranceContractsMember" xlink:label="asrv_AnnuityInsuranceContractsMember_1" xlink:title="asrv_AnnuityInsuranceContractsMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentIssuerNameDomain_30" xlink:to="asrv_AnnuityInsuranceContractsMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentIssuerNameDomain_30 To asrv_AnnuityInsuranceContractsMember_1" order="29" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="us-gaap_InvestmentTypeCategorizationMember_3" xlink:title="us-gaap_InvestmentTypeCategorizationMember_3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember" xlink:label="us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember_1" xlink:title="us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentTypeCategorizationMember_3" xlink:to="us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentTypeCategorizationMember_3 To us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember_1" order="4" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="us-gaap_InvestmentTypeCategorizationMember_4" xlink:title="us-gaap_InvestmentTypeCategorizationMember_4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MutualFundMember" xlink:label="us-gaap_MutualFundMember_1" xlink:title="us-gaap_MutualFundMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentTypeCategorizationMember_4" xlink:to="us-gaap_MutualFundMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentTypeCategorizationMember_4 To us-gaap_MutualFundMember_1" order="5" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="us-gaap_InvestmentTypeCategorizationMember_5" xlink:title="us-gaap_InvestmentTypeCategorizationMember_5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" xlink:label="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember_2" xlink:title="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember_2" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentTypeCategorizationMember_5" xlink:to="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember_2" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentTypeCategorizationMember_5 To us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember_2" order="6" priority="0" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="us-gaap_InvestmentTypeCategorizationMember_6" xlink:title="us-gaap_InvestmentTypeCategorizationMember_6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MoneyMarketFundsMember" xlink:label="us-gaap_MoneyMarketFundsMember_1" xlink:title="us-gaap_MoneyMarketFundsMember_1" />
    <link:definitionArc xlink:type="arc" xlink:from="us-gaap_InvestmentTypeCategorizationMember_6" xlink:to="us-gaap_MoneyMarketFundsMember_1" use="optional" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:title="definition:us-gaap_InvestmentTypeCategorizationMember_6 To us-gaap_MoneyMarketFundsMember_1" order="7" priority="0" />
  </link:definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DocumentDocumentAndEntityInformation" xlink:type="extended" xlink:title="00090 - Document - Document and Entity Information" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentInformationTable" xlink:label="dei_DocumentInformationTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="dei_DocumentInformationTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentInformationLineItems" xlink:label="dei_DocumentInformationLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_DocumentInformationTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentType" xlink:label="dei_DocumentType" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_DocumentType" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityRegistrantName" xlink:label="dei_EntityRegistrantName" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityRegistrantName" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityCentralIndexKey" xlink:label="dei_EntityCentralIndexKey" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityCentralIndexKey" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_AmendmentFlag" xlink:label="dei_AmendmentFlag" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_AmendmentFlag" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/StatementStatementsOfNetAssetsAvailableForBenefits" xlink:type="extended" xlink:title="00100 - Statement - STATEMENTS OF NET ASSETS AVAILABLE FOR BENEFITS" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanStatementOfNetAssetAvailableForBenefitTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanStatementOfNetAssetAvailableForBenefitTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanStatementOfNetAssetAvailableForBenefitTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis" xlink:label="us-gaap_InvestmentTypeAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanStatementOfNetAssetAvailableForBenefitTable" xlink:to="us-gaap_InvestmentTypeAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="us-gaap_InvestmentTypeCategorizationMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="us-gaap_InvestmentTypeAxis" xlink:to="us-gaap_InvestmentTypeCategorizationMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" xlink:label="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MutualFundMember" xlink:label="us-gaap_MutualFundMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap_MutualFundMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember" xlink:label="us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MoneyMarketFundsMember" xlink:label="us-gaap_MoneyMarketFundsMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap_MoneyMarketFundsMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanStatementOfNetAssetAvailableForBenefitLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanStatementOfNetAssetAvailableForBenefitLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanStatementOfNetAssetAvailableForBenefitLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanStatementOfNetAssetAvailableForBenefitTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAssetAbstract" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAssetAbstract" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanStatementOfNetAssetAvailableForBenefitLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanAssetAbstract" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAbstract" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAbstract" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAssetAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAbstract" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustContractValue" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustContractValue" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAssetAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustContractValue" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairAndContractValue" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairAndContractValue" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAssetAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairAndContractValue" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanCash" xlink:label="us-gaap-ebp_EmployeeBenefitPlanCash" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAssetAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanCash" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipant" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipant" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAssetAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipant" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanEmployerContributionReceivable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanEmployerContributionReceivable" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="6" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAssetAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanEmployerContributionReceivable" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanParticipantContributionReceivable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanParticipantContributionReceivable" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="7" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAssetAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanParticipantContributionReceivable" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanAccruedInterestReceivable" xlink:label="asrv_EmployeeBenefitPlanAccruedInterestReceivable" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="8" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAssetAbstract" xlink:to="asrv_EmployeeBenefitPlanAccruedInterestReceivable" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAsset" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAsset" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="9" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAssetAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanAsset" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanStatementOfNetAssetAvailableForBenefitLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/StatementStatementsOfChangesInNetAssetsAvailableForBenefits" xlink:type="extended" xlink:title="00200 - Statement - STATEMENTS OF CHANGES IN NET ASSETS AVAILABLE FOR BENEFITS" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanStatementOfChangeInNetAssetAvailableForBenefitTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanStatementOfChangeInNetAssetAvailableForBenefitTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanStatementOfChangeInNetAssetAvailableForBenefitTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanStatementOfChangeInNetAssetAvailableForBenefitLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanStatementOfChangeInNetAssetAvailableForBenefitLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanStatementOfChangeInNetAssetAvailableForBenefitLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanStatementOfChangeInNetAssetAvailableForBenefitTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseAbstract" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseAbstract" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanStatementOfChangeInNetAssetAvailableForBenefitLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseAbstract" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestmentAbstract" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestmentAbstract" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestmentAbstract" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForGainLossOnInvestment" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForGainLossOnInvestment" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestmentAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForGainLossOnInvestment" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForInterestAndDividendIncomeOnInvestment" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForInterestAndDividendIncomeOnInvestment" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestmentAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForInterestAndDividendIncomeOnInvestment" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestment" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestment" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestmentAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestment" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForInterestIncomeOnNoteReceivableFromParticipant" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForInterestIncomeOnNoteReceivableFromParticipant" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForInterestIncomeOnNoteReceivableFromParticipant" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForContributionAbstract" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForContributionAbstract" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForContributionAbstract" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContributionExcludingRollover" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContributionExcludingRollover" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForContributionAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContributionExcludingRollover" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForEmployerContribution" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForEmployerContribution" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForContributionAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForEmployerContribution" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContributionRollover" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContributionRollover" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForContributionAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContributionRollover" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForContribution" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForContribution" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForContributionAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForContribution" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncrease" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncrease" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncrease" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseAbstract" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseAbstract" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanStatementOfChangeInNetAssetAvailableForBenefitLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseAbstract" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForPaymentToParticipant" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForPaymentToParticipant" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForPaymentToParticipant" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForAdministrativeExpense" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForAdministrativeExpense" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForAdministrativeExpense" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecrease" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecrease" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseAbstract" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecrease" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecrease" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecrease" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap-ebp_EmployeeBenefitPlanStatementOfChangeInNetAssetAvailableForBenefitLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecrease" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="us-gaap-ebp_EmployeeBenefitPlanStatementOfChangeInNetAssetAvailableForBenefitLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureDescriptionOfPlan" xlink:type="extended" xlink:title="10101 - Disclosure - DESCRIPTION OF PLAN" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTextBlock" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureSummaryOfSignificantAccountingPolicies" xlink:type="extended" xlink:title="10201 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanSummaryOfAccountingPolicyTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanSummaryOfAccountingPolicyTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanSummaryOfAccountingPolicyTextBlock" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosurePlanTermination" xlink:type="extended" xlink:title="10301 - Disclosure - PLAN TERMINATION" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanPlanTerminationTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanPlanTerminationTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanPlanTerminationTextBlock" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureTaxStatus" xlink:type="extended" xlink:title="10401 - Disclosure - TAX STATUS" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanTaxStatusTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanTaxStatusTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanTaxStatusTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanTaxStatusLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanTaxStatusLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanTaxStatusLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanTaxStatusTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanTaxStatusTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanTaxStatusTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanTaxStatusLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanTaxStatusTextBlock" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosurePartyInInterestTransactions" xlink:type="extended" xlink:title="10501 - Disclosure - PARTY-IN-INTEREST TRANSACTIONS" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsTextBlock" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureFairValueMeasurements" xlink:type="extended" xlink:title="10601 - Disclosure - FAIR VALUE MEASUREMENTS" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTextBlock" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureFairValueOfFinancialInstruments" xlink:type="extended" xlink:title="10701 - Disclosure - FAIR VALUE OF FINANCIAL INSTRUMENTS" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanFairValueOfFinancialInstrumentsTextBlock" xlink:label="asrv_EmployeeBenefitPlanFairValueOfFinancialInstrumentsTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:to="asrv_EmployeeBenefitPlanFairValueOfFinancialInstrumentsTextBlock" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureFullyBenefitResponsiveInvestmentContract" xlink:type="extended" xlink:title="10801 - Disclosure - FULLY BENEFIT-RESPONSIVE INVESTMENT CONTRACT" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanFullyBenefitResponsiveInvestmentContractTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanFullyBenefitResponsiveInvestmentContractTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanFullyBenefitResponsiveInvestmentContractTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanFullyBenefitResponsiveInvestmentContractLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanFullyBenefitResponsiveInvestmentContractLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanFullyBenefitResponsiveInvestmentContractLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanFullyBenefitResponsiveInvestmentContractTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanFullyBenefitResponsiveInvestmentContractTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanFullyBenefitResponsiveInvestmentContractTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanFullyBenefitResponsiveInvestmentContractLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanFullyBenefitResponsiveInvestmentContractTextBlock" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureRiskAndUncertainties" xlink:type="extended" xlink:title="10901 - Disclosure - RISK AND UNCERTAINTIES" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EbpRiskAndUncertaintyTable" xlink:label="us-gaap-ebp_EbpRiskAndUncertaintyTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EbpRiskAndUncertaintyTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EbpRiskAndUncertaintyLineItems" xlink:label="us-gaap-ebp_EbpRiskAndUncertaintyLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EbpRiskAndUncertaintyLineItems" xlink:to="us-gaap-ebp_EbpRiskAndUncertaintyTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanRiskAndUncertaintyTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanRiskAndUncertaintyTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EbpRiskAndUncertaintyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanRiskAndUncertaintyTextBlock" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureScheduleHLine4iScheduleOfAssetsHeldAtEndOfYear" xlink:type="extended" xlink:title="11001 - Disclosure - SCHEDULE H, LINE 4i - SCHEDULE OF ASSETS (HELD AT END OF YEAR)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTableTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTableTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTableTextBlock" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureSummaryOfSignificantAccountingPoliciesPolicies" xlink:type="extended" xlink:title="20202 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanBasisOfAccountingPolicyTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanBasisOfAccountingPolicyTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanBasisOfAccountingPolicyTextBlock" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanUseOfEstimatePolicyTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanUseOfEstimatePolicyTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanUseOfEstimatePolicyTextBlock" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentPolicyTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentPolicyTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentPolicyTextBlock" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantPolicyTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantPolicyTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantPolicyTextBlock" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanPaymentToParticipantPolicyTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanPaymentToParticipantPolicyTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="6" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanPaymentToParticipantPolicyTextBlock" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanContributionPolicyTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanContributionPolicyTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="7" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanContributionPolicyTextBlock" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanExpensePolicyTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanExpensePolicyTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="8" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanExpensePolicyTextBlock" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureFairValueMeasurementsTables" xlink:type="extended" xlink:title="30603 - Disclosure - FAIR VALUE MEASUREMENTS (Tables)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTableTextBlock" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTableTextBlock" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTableTextBlock" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureDescriptionOfPlanDetails" xlink:type="extended" xlink:title="40101 - Disclosure - DESCRIPTION OF PLAN (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StatementScenarioAxis" xlink:label="srt_StatementScenarioAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:to="srt_StatementScenarioAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScenarioUnspecifiedDomain" xlink:label="srt_ScenarioUnspecifiedDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="srt_StatementScenarioAxis" xlink:to="srt_ScenarioUnspecifiedDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_NonUnionAndUnionEmployeesHiredBeforeJanuary12013AndJanuary12024RespectivelyMember" xlink:label="asrv_NonUnionAndUnionEmployeesHiredBeforeJanuary12013AndJanuary12024RespectivelyMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="srt_ScenarioUnspecifiedDomain" xlink:to="asrv_NonUnionAndUnionEmployeesHiredBeforeJanuary12013AndJanuary12024RespectivelyMember" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_NonUnionAndUnionEmployeesHiredOrRehiredAfterJanuary12013AndJanuary12024RespectivelyMember" xlink:label="asrv_NonUnionAndUnionEmployeesHiredOrRehiredAfterJanuary12013AndJanuary12024RespectivelyMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="srt_ScenarioUnspecifiedDomain" xlink:to="asrv_NonUnionAndUnionEmployeesHiredOrRehiredAfterJanuary12013AndJanuary12024RespectivelyMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionAvailable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionAvailable" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanDescriptionAvailable" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanMinimumAgeForPlanEligibility" xlink:label="asrv_EmployeeBenefitPlanMinimumAgeForPlanEligibility" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="asrv_EmployeeBenefitPlanMinimumAgeForPlanEligibility" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanComputationPeriodForMinimumServicePeriod" xlink:label="asrv_EmployeeBenefitPlanComputationPeriodForMinimumServicePeriod" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="asrv_EmployeeBenefitPlanComputationPeriodForMinimumServicePeriod" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanMinimumServicePeriodForPlanEligibility" xlink:label="asrv_EmployeeBenefitPlanMinimumServicePeriodForPlanEligibility" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="asrv_EmployeeBenefitPlanMinimumServicePeriodForPlanEligibility" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanMinimumServicePeriodForDiscretionaryEmployerContribution" xlink:label="asrv_EmployeeBenefitPlanMinimumServicePeriodForDiscretionaryEmployerContribution" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="6" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="asrv_EmployeeBenefitPlanMinimumServicePeriodForDiscretionaryEmployerContribution" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureDescriptionOfPlanContributionsDetails" xlink:type="extended" xlink:title="40102 - Disclosure - DESCRIPTION OF PLAN - Contributions (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StatementScenarioAxis" xlink:label="srt_StatementScenarioAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:to="srt_StatementScenarioAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScenarioUnspecifiedDomain" xlink:label="srt_ScenarioUnspecifiedDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="srt_StatementScenarioAxis" xlink:to="srt_ScenarioUnspecifiedDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_NonUnionEmployeesHiredAfterDecember312012Member" xlink:label="asrv_NonUnionEmployeesHiredAfterDecember312012Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="srt_ScenarioUnspecifiedDomain" xlink:to="asrv_NonUnionEmployeesHiredAfterDecember312012Member" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_NonUnionEmployeesHiredOnOrDecember312012Member" xlink:label="asrv_NonUnionEmployeesHiredOnOrDecember312012Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="srt_ScenarioUnspecifiedDomain" xlink:to="asrv_NonUnionEmployeesHiredOnOrDecember312012Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis" xlink:label="srt_RangeAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:to="srt_RangeAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember" xlink:label="srt_RangeMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="srt_RangeAxis" xlink:to="srt_RangeMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember" xlink:label="srt_MinimumMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="srt_RangeMember" xlink:to="srt_MinimumMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember" xlink:label="srt_MaximumMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="srt_RangeMember" xlink:to="srt_MaximumMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanParticipantContributionPretaxMaximumAnnualCompensationToTotalCompensationPercentage" xlink:label="us-gaap-ebp_EmployeeBenefitPlanParticipantContributionPretaxMaximumAnnualCompensationToTotalCompensationPercentage" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanParticipantContributionPretaxMaximumAnnualCompensationToTotalCompensationPercentage" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanEmployerContributionMatchingPercentage" xlink:label="us-gaap-ebp_EmployeeBenefitPlanEmployerContributionMatchingPercentage" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanEmployerContributionMatchingPercentage" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanEmployerContributionParticipantCompensationMatchedPercentage" xlink:label="us-gaap-ebp_EmployeeBenefitPlanEmployerContributionParticipantCompensationMatchedPercentage" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanEmployerContributionParticipantCompensationMatchedPercentage" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanEmployerContributionParticipantCompensationNonElectiveContributionPercentage" xlink:label="asrv_EmployeeBenefitPlanEmployerContributionParticipantCompensationNonElectiveContributionPercentage" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="asrv_EmployeeBenefitPlanEmployerContributionParticipantCompensationNonElectiveContributionPercentage" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanEmployeeContributionIncrementalPercentage" xlink:label="asrv_EmployeeBenefitPlanEmployeeContributionIncrementalPercentage" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="6" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="asrv_EmployeeBenefitPlanEmployeeContributionIncrementalPercentage" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanNumberOfMutualFunds" xlink:label="asrv_EmployeeBenefitPlanNumberOfMutualFunds" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="7" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="asrv_EmployeeBenefitPlanNumberOfMutualFunds" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanNumberOfCommonCollectivePortfolios" xlink:label="asrv_EmployeeBenefitPlanNumberOfCommonCollectivePortfolios" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="8" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="asrv_EmployeeBenefitPlanNumberOfCommonCollectivePortfolios" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanNumberOfMoneyMarketAndCashEquivalentFunds" xlink:label="asrv_EmployeeBenefitPlanNumberOfMoneyMarketAndCashEquivalentFunds" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="9" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="asrv_EmployeeBenefitPlanNumberOfMoneyMarketAndCashEquivalentFunds" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureDescriptionOfPlanVestingDetails" xlink:type="extended" xlink:title="40103 - Disclosure - DESCRIPTION OF PLAN - Vesting (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanMinimumServicePeriodConsideredForCreditedServiceYear" xlink:label="asrv_EmployeeBenefitPlanMinimumServicePeriodConsideredForCreditedServiceYear" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="asrv_EmployeeBenefitPlanMinimumServicePeriodConsideredForCreditedServiceYear" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanVestingPercentage" xlink:label="asrv_EmployeeBenefitPlanVestingPercentage" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="asrv_EmployeeBenefitPlanVestingPercentage" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanVestingPeriod" xlink:label="asrv_EmployeeBenefitPlanVestingPeriod" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="asrv_EmployeeBenefitPlanVestingPeriod" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureDescriptionOfPlanNotesReceivableFromParticipantsDetails" xlink:type="extended" xlink:title="40104 - Disclosure - DESCRIPTION OF PLAN - Notes Receivable from Participants (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis" xlink:label="srt_RangeAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:to="srt_RangeAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember" xlink:label="srt_RangeMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="srt_RangeAxis" xlink:to="srt_RangeMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember" xlink:label="srt_MinimumMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="srt_RangeMember" xlink:to="srt_MinimumMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember" xlink:label="srt_MaximumMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="srt_RangeMember" xlink:to="srt_MaximumMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMinimumBorrowingAmount" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMinimumBorrowingAmount" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMinimumBorrowingAmount" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingAmount" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingAmount" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingAmount" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingToTotalAccountPercentage" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingToTotalAccountPercentage" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingToTotalAccountPercentage" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanNoteReceivableFromParticipantTerm" xlink:label="asrv_EmployeeBenefitPlanNoteReceivableFromParticipantTerm" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="asrv_EmployeeBenefitPlanNoteReceivableFromParticipantTerm" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanParticipantLoanInterestRate" xlink:label="us-gaap-ebp_EmployeeBenefitPlanParticipantLoanInterestRate" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="6" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanParticipantLoanInterestRate" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureDescriptionOfPlanPaymentOfBenefitsAndForfeituresDetails" xlink:type="extended" xlink:title="40105 - Disclosure - DESCRIPTION OF PLAN - Payment of benefits and forfeitures (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanParticipantAgeForWithdrawalFromAccountBalance" xlink:label="asrv_EmployeeBenefitPlanParticipantAgeForWithdrawalFromAccountBalance" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="asrv_EmployeeBenefitPlanParticipantAgeForWithdrawalFromAccountBalance" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanMaximumBreakInServicePeriod" xlink:label="asrv_EmployeeBenefitPlanMaximumBreakInServicePeriod" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="asrv_EmployeeBenefitPlanMaximumBreakInServicePeriod" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanForfeitedNonvestedAccount" xlink:label="us-gaap-ebp_EmployeeBenefitPlanForfeitedNonvestedAccount" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanForfeitedNonvestedAccount" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanForfeitedNonvestedAccountDecreaseForAdministrativeExpense" xlink:label="us-gaap-ebp_EmployeeBenefitPlanForfeitedNonvestedAccountDecreaseForAdministrativeExpense" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanForfeitedNonvestedAccountDecreaseForAdministrativeExpense" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureSummaryOfSignificantAccountingPoliciesDetails" xlink:type="extended" xlink:title="40201 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestAxis" xlink:label="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyTable" xlink:to="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestDomain" xlink:label="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestAxis" xlink:to="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyMember" xlink:label="us-gaap_RelatedPartyMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestDomain" xlink:to="us-gaap_RelatedPartyMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAllowanceForCreditLoss" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAllowanceForCreditLoss" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAllowanceForCreditLoss" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseFromPaymentToDefaultedParticipantLoans" xlink:label="asrv_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseFromPaymentToDefaultedParticipantLoans" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:to="asrv_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseFromPaymentToDefaultedParticipantLoans" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanExcessContributionPayable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanExcessContributionPayable" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanExcessContributionPayable" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanAdministrativeExpensePaidByEmployer" xlink:label="asrv_EmployeeBenefitPlanAdministrativeExpensePaidByEmployer" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems" xlink:to="asrv_EmployeeBenefitPlanAdministrativeExpensePaidByEmployer" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosurePlanTerminationDetails" xlink:type="extended" xlink:title="40301 - Disclosure - PLAN TERMINATION (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanVestingPercentageInEventPlanTermination" xlink:label="asrv_EmployeeBenefitPlanVestingPercentageInEventPlanTermination" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems" xlink:to="asrv_EmployeeBenefitPlanVestingPercentageInEventPlanTermination" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureTaxStatusDetails" xlink:type="extended" xlink:title="40401 - Disclosure - TAX STATUS (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanTaxStatusTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanTaxStatusTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanTaxStatusTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanTaxStatusLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanTaxStatusLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanTaxStatusLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanTaxStatusTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanTaxDeterminationLetterObtained" xlink:label="us-gaap-ebp_EmployeeBenefitPlanTaxDeterminationLetterObtained" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanTaxStatusLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanTaxDeterminationLetterObtained" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanTaxDeterminationLetterDate" xlink:label="us-gaap-ebp_EmployeeBenefitPlanTaxDeterminationLetterDate" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanTaxStatusLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanTaxDeterminationLetterDate" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosurePartyInInterestTransactionsDetails" xlink:type="extended" xlink:title="40501 - Disclosure - PARTY-IN-INTEREST TRANSACTIONS (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis" xlink:label="us-gaap_InvestmentTypeAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsTable" xlink:to="us-gaap_InvestmentTypeAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="us-gaap_InvestmentTypeCategorizationMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="us-gaap_InvestmentTypeAxis" xlink:to="us-gaap_InvestmentTypeCategorizationMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" xlink:label="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember" xlink:label="us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestAxis" xlink:label="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsTable" xlink:to="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestDomain" xlink:label="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestAxis" xlink:to="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanTrusteeMember" xlink:label="us-gaap-ebp_EmployeeBenefitPlanTrusteeMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestDomain" xlink:to="us-gaap-ebp_EmployeeBenefitPlanTrusteeMember" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanSponsorMember" xlink:label="asrv_EmployeeBenefitPlanSponsorMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestDomain" xlink:to="asrv_EmployeeBenefitPlanSponsorMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EbpRiskAndUncertaintyLineItems" xlink:label="us-gaap-ebp_EbpRiskAndUncertaintyLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EbpRiskAndUncertaintyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EbpRiskAndUncertaintyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EbpRiskAndUncertaintyConcentrationOfInvestmentAtFairValueToNetAssetsPercentage" xlink:label="us-gaap-ebp_EbpRiskAndUncertaintyConcentrationOfInvestmentAtFairValueToNetAssetsPercentage" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EbpRiskAndUncertaintyLineItems" xlink:to="us-gaap-ebp_EbpRiskAndUncertaintyConcentrationOfInvestmentAtFairValueToNetAssetsPercentage" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentNumberOfShares" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentNumberOfShares" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap-ebp_EbpRiskAndUncertaintyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentNumberOfShares" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForDividendIncomeOnInvestment" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForDividendIncomeOnInvestment" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="us-gaap-ebp_EbpRiskAndUncertaintyLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForDividendIncomeOnInvestment" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureFairValueMeasurementsDetails" xlink:type="extended" xlink:title="40601 - Disclosure - FAIR VALUE MEASUREMENTS (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis" xlink:label="us-gaap_InvestmentTypeAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" xlink:to="us-gaap_InvestmentTypeAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="us-gaap_InvestmentTypeCategorizationMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="us-gaap_InvestmentTypeAxis" xlink:to="us-gaap_InvestmentTypeCategorizationMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MutualFundMember" xlink:label="us-gaap_MutualFundMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap_MutualFundMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember" xlink:label="us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MoneyMarketFundsMember" xlink:label="us-gaap_MoneyMarketFundsMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap_MoneyMarketFundsMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" xlink:to="us-gaap_FairValueByFairValueHierarchyLevelAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:to="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel12And3Member" xlink:label="us-gaap_FairValueInputsLevel12And3Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:to="us-gaap_FairValueInputsLevel12And3Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel1Member" xlink:label="us-gaap_FairValueInputsLevel1Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:to="us-gaap_FairValueInputsLevel1Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasuredAtNetAssetValuePerShareMember" xlink:label="us-gaap_FairValueMeasuredAtNetAssetValuePerShareMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:to="us-gaap_FairValueMeasuredAtNetAssetValuePerShareMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureFairValueMeasurementsNarrativeDetails" xlink:type="extended" xlink:title="40602 - Disclosure - FAIR VALUE MEASUREMENTS - Narrative (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis" xlink:label="us-gaap_InvestmentTypeAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" xlink:to="us-gaap_InvestmentTypeAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="us-gaap_InvestmentTypeCategorizationMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="us-gaap_InvestmentTypeAxis" xlink:to="us-gaap_InvestmentTypeCategorizationMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" xlink:label="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EmployeeBenefitPlanFederatedHermesCapitalPreservationFundMember" xlink:label="asrv_EmployeeBenefitPlanFederatedHermesCapitalPreservationFundMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" xlink:to="asrv_EmployeeBenefitPlanFederatedHermesCapitalPreservationFundMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" xlink:to="us-gaap_FairValueByFairValueHierarchyLevelAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:to="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasuredAtNetAssetValuePerShareMember" xlink:label="us-gaap_FairValueMeasuredAtNetAssetValuePerShareMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:to="us-gaap_FairValueMeasuredAtNetAssetValuePerShareMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanNetAssetValuePerShareOrUnit" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNetAssetValuePerShareOrUnit" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanNetAssetValuePerShareOrUnit" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EbpFairValueInvestmentNavUnfundedCommitment" xlink:label="us-gaap-ebp_EbpFairValueInvestmentNavUnfundedCommitment" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:to="us-gaap-ebp_EbpFairValueInvestmentNavUnfundedCommitment" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EbpFairValueInvestmentNavRedemptionNoticePeriod" xlink:label="us-gaap-ebp_EbpFairValueInvestmentNavRedemptionNoticePeriod" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavLineItems" xlink:to="us-gaap-ebp_EbpFairValueInvestmentNavRedemptionNoticePeriod" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureRiskAndUncertaintiesDetails" xlink:type="extended" xlink:title="40901 - Disclosure - RISK AND UNCERTAINTIES (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EbpRiskAndUncertaintyTable" xlink:label="us-gaap-ebp_EbpRiskAndUncertaintyTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EbpRiskAndUncertaintyTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis" xlink:label="us-gaap_InvestmentTypeAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="2" xlink:from="us-gaap-ebp_EbpRiskAndUncertaintyTable" xlink:to="us-gaap_InvestmentTypeAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="us-gaap_InvestmentTypeCategorizationMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="us-gaap_InvestmentTypeAxis" xlink:to="us-gaap_InvestmentTypeCategorizationMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" xlink:label="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameAxis" xlink:label="us-gaap_InvestmentIssuerNameAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="3" xlink:from="us-gaap-ebp_EbpRiskAndUncertaintyTable" xlink:to="us-gaap_InvestmentIssuerNameAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain" xlink:label="us-gaap_InvestmentIssuerNameDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="us-gaap_InvestmentIssuerNameAxis" xlink:to="us-gaap_InvestmentIssuerNameDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_PathroadTacticalCapitalAppreciationIncomeMember" xlink:label="asrv_PathroadTacticalCapitalAppreciationIncomeMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_InvestmentIssuerNameDomain" xlink:to="asrv_PathroadTacticalCapitalAppreciationIncomeMember" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_PathroadTacticalBalancedGrowthIncomeMember" xlink:label="asrv_PathroadTacticalBalancedGrowthIncomeMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_InvestmentIssuerNameDomain" xlink:to="asrv_PathroadTacticalBalancedGrowthIncomeMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EbpRiskAndUncertaintyLineItems" xlink:label="us-gaap-ebp_EbpRiskAndUncertaintyLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EbpRiskAndUncertaintyLineItems" xlink:to="us-gaap-ebp_EbpRiskAndUncertaintyTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EbpRiskAndUncertaintyConcentrationOfInvestmentAtFairValueToNetAssetsAmount" xlink:label="us-gaap-ebp_EbpRiskAndUncertaintyConcentrationOfInvestmentAtFairValueToNetAssetsAmount" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EbpRiskAndUncertaintyLineItems" xlink:to="us-gaap-ebp_EbpRiskAndUncertaintyConcentrationOfInvestmentAtFairValueToNetAssetsAmount" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EbpRiskAndUncertaintyConcentrationOfInvestmentBenchmarkThresholdPercentage" xlink:label="us-gaap-ebp_EbpRiskAndUncertaintyConcentrationOfInvestmentBenchmarkThresholdPercentage" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EbpRiskAndUncertaintyLineItems" xlink:to="us-gaap-ebp_EbpRiskAndUncertaintyConcentrationOfInvestmentBenchmarkThresholdPercentage" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureScheduleHLine4iScheduleOfAssetsHeldAtEndOfYearDetails" xlink:type="extended" xlink:title="41001 - Disclosure - SCHEDULE H, LINE 4i - SCHEDULE OF ASSETS (HELD AT END OF YEAR) (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis" xlink:label="srt_RangeAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" xlink:to="srt_RangeAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember" xlink:label="srt_RangeMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="srt_RangeAxis" xlink:to="srt_RangeMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember" xlink:label="srt_MinimumMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="srt_RangeMember" xlink:to="srt_MinimumMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember" xlink:label="srt_MaximumMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="srt_RangeMember" xlink:to="srt_MaximumMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis" xlink:label="us-gaap_InvestmentTypeAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" xlink:to="us-gaap_InvestmentTypeAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="us-gaap_InvestmentTypeCategorizationMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="us-gaap_InvestmentTypeAxis" xlink:to="us-gaap_InvestmentTypeCategorizationMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember" xlink:label="us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MutualFundMember" xlink:label="us-gaap_MutualFundMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap_MutualFundMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" xlink:label="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MoneyMarketFundsMember" xlink:label="us-gaap_MoneyMarketFundsMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap_MoneyMarketFundsMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIdentifierAxis" xlink:label="us-gaap_InvestmentIdentifierAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="4" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" xlink:to="us-gaap_InvestmentIdentifierAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityTaxIdentificationNumber" xlink:label="dei_EntityTaxIdentificationNumber" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="dei_EntityTaxIdentificationNumber" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanPlanNumber" xlink:label="us-gaap-ebp_EmployeeBenefitPlanPlanNumber" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanPlanNumber" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentPartyInInterest" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentPartyInInterest" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentPartyInInterest" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentIssuerNameExtensibleEnumeration" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentIssuerNameExtensibleEnumeration" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentIssuerNameExtensibleEnumeration" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentTypeExtensibleEnumeration" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentTypeExtensibleEnumeration" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="6" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentTypeExtensibleEnumeration" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentInvestmentExcludingPlanInterestInMasterTrustParticipationStatusExtensibleEnumeration" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentInvestmentExcludingPlanInterestInMasterTrustParticipationStatusExtensibleEnumeration" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="7" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentInvestmentExcludingPlanInterestInMasterTrustParticipationStatusExtensibleEnumeration" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentInvestmentExcludingPlanInterestInMasterTrustCurrentValue" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentInvestmentExcludingPlanInterestInMasterTrustCurrentValue" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="8" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentInvestmentExcludingPlanInterestInMasterTrustCurrentValue" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanParticipantLoanInterestRate" xlink:label="us-gaap-ebp_EmployeeBenefitPlanParticipantLoanInterestRate" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="9" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanParticipantLoanInterestRate" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanParticipantLoanMaturityDate" xlink:label="us-gaap-ebp_EmployeeBenefitPlanParticipantLoanMaturityDate" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="10" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanParticipantLoanMaturityDate" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentParticipantLoanAfterDeemedDistribution" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentParticipantLoanAfterDeemedDistribution" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="11" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentParticipantLoanAfterDeemedDistribution" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestment" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestment" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="12" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestment" priority="1" use="optional" />
  </definitionLink>
  <definitionLink xlink:role="http://www.ameriserv.com/role/DisclosureScheduleHLine4iScheduleOfAssetsHeldAtEndOfYearDefaultDetails" xlink:type="extended" xlink:title="41001 - Disclosure - SCHEDULE H, LINE 4i - SCHEDULE OF ASSETS (HELD AT END OF YEAR) Default (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" xlink:label="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" xlink:to="dei_LegalEntityAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="dei_EntityDomain" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="dei_LegalEntityAxis" xlink:to="dei_EntityDomain" use="optional" />
    <loc xlink:type="locator" xlink:href="asrv-20251231.xsd#asrv_EBP002Member" xlink:label="asrv_EBP002Member" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="dei_EntityDomain" xlink:to="asrv_EBP002Member" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis" xlink:label="srt_RangeAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" xlink:to="srt_RangeAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember" xlink:label="srt_RangeMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="srt_RangeAxis" xlink:to="srt_RangeMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember" xlink:label="srt_MinimumMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="srt_RangeMember" xlink:to="srt_MinimumMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember" xlink:label="srt_MaximumMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="srt_RangeMember" xlink:to="srt_MaximumMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis" xlink:label="us-gaap_InvestmentTypeAxis" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" xlink:to="us-gaap_InvestmentTypeAxis" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="us-gaap_InvestmentTypeCategorizationMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" order="1" xlink:from="us-gaap_InvestmentTypeAxis" xlink:to="us-gaap_InvestmentTypeCategorizationMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember" xlink:label="us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="1" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap-ebp_EmployeeBenefitPlanEmployerCommonStockMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MutualFundMember" xlink:label="us-gaap_MutualFundMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap_MutualFundMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" xlink:label="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MoneyMarketFundsMember" xlink:label="us-gaap_MoneyMarketFundsMember" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap_InvestmentTypeCategorizationMember" xlink:to="us-gaap_MoneyMarketFundsMember" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:label="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" order="1" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable" use="optional" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityTaxIdentificationNumber" xlink:label="dei_EntityTaxIdentificationNumber" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="2" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="dei_EntityTaxIdentificationNumber" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanPlanNumber" xlink:label="us-gaap-ebp_EmployeeBenefitPlanPlanNumber" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="3" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanPlanNumber" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentPartyInInterest" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentPartyInInterest" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="4" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentPartyInInterest" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentIssuerNameExtensibleEnumeration" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentIssuerNameExtensibleEnumeration" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="5" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentIssuerNameExtensibleEnumeration" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanInvestmentTypeExtensibleEnumeration" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentTypeExtensibleEnumeration" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="6" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanInvestmentTypeExtensibleEnumeration" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentInvestmentExcludingPlanInterestInMasterTrustParticipationStatusExtensibleEnumeration" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentInvestmentExcludingPlanInterestInMasterTrustParticipationStatusExtensibleEnumeration" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="7" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentInvestmentExcludingPlanInterestInMasterTrustParticipationStatusExtensibleEnumeration" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentInvestmentExcludingPlanInterestInMasterTrustCurrentValue" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentInvestmentExcludingPlanInterestInMasterTrustCurrentValue" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="8" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentInvestmentExcludingPlanInterestInMasterTrustCurrentValue" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanParticipantLoanInterestRate" xlink:label="us-gaap-ebp_EmployeeBenefitPlanParticipantLoanInterestRate" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="9" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanParticipantLoanInterestRate" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanParticipantLoanMaturityDate" xlink:label="us-gaap-ebp_EmployeeBenefitPlanParticipantLoanMaturityDate" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="10" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanParticipantLoanMaturityDate" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentParticipantLoanAfterDeemedDistribution" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentParticipantLoanAfterDeemedDistribution" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="11" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestmentParticipantLoanAfterDeemedDistribution" priority="1" use="optional" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/ebp/elts/us-gaap-ebp-2026.xsd#us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestment" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestment" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" order="12" xlink:from="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems" xlink:to="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestment" priority="1" use="optional" />
  </definitionLink>
</link:linkbase>
