<?xml version="1.0" encoding="utf-8"?>
<!--XBRL document created with Toppan Merrill Bridge  11.4.0.1 -->
<!--Based on XBRL 2.1-->
<!--Created on: 8/4/2026 4:46:17 PM-->
<!--Modified on: 8/4/2026 4:46:17 PM-->
<link:linkbase xmlns="http://www.xbrl.org/2003/linkbase" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" 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:xbrli="http://www.xbrl.org/2003/instance">
  <link:roleRef xlink:type="simple" xlink:href="verx-20260630.xsd#StatementCondensedConsolidatedBalanceSheets" roleURI="http://www.deitaxonomy.com/role/StatementCondensedConsolidatedBalanceSheets" />
  <link:roleRef xlink:type="simple" xlink:href="verx-20260630.xsd#StatementCondensedConsolidatedStatementsOfComprehensiveIncomeLoss" roleURI="http://www.deitaxonomy.com/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncomeLoss" />
  <link:roleRef xlink:type="simple" xlink:href="verx-20260630.xsd#StatementCondensedConsolidatedStatementsOfCashFlows" roleURI="http://www.deitaxonomy.com/role/StatementCondensedConsolidatedStatementsOfCashFlows" />
  <link:roleRef xlink:type="simple" xlink:href="verx-20260630.xsd#StatementCondensedConsolidatedStatementsOfCashFlowsParenthetical" roleURI="http://www.deitaxonomy.com/role/StatementCondensedConsolidatedStatementsOfCashFlowsParenthetical" />
  <link:roleRef xlink:type="simple" xlink:href="verx-20260630.xsd#DisclosureSummaryOfSignificantAccountingPoliciesSupplementalBalanceSheetDisclosuresDetails" roleURI="http://www.deitaxonomy.com/role/DisclosureSummaryOfSignificantAccountingPoliciesSupplementalBalanceSheetDisclosuresDetails" />
  <link:roleRef xlink:type="simple" xlink:href="verx-20260630.xsd#DisclosureAcquisitionsFairValueOfAssetsAcquiredAndLiabilitiesAssumedDetails" roleURI="http://www.deitaxonomy.com/role/DisclosureAcquisitionsFairValueOfAssetsAcquiredAndLiabilitiesAssumedDetails" />
  <link:roleRef xlink:type="simple" xlink:href="verx-20260630.xsd#DisclosurePropertyAndEquipmentDetails" roleURI="http://www.deitaxonomy.com/role/DisclosurePropertyAndEquipmentDetails" />
  <link:roleRef xlink:type="simple" xlink:href="verx-20260630.xsd#DisclosurePropertyAndEquipmentMajorComponentsOfInternalUseSoftwareDetails" roleURI="http://www.deitaxonomy.com/role/DisclosurePropertyAndEquipmentMajorComponentsOfInternalUseSoftwareDetails" />
  <link:roleRef xlink:type="simple" xlink:href="verx-20260630.xsd#DisclosureCapitalizedSoftwareDetails" roleURI="http://www.deitaxonomy.com/role/DisclosureCapitalizedSoftwareDetails" />
  <link:roleRef xlink:type="simple" xlink:href="verx-20260630.xsd#DisclosureGoodwillAndOtherIntangibleAssetsDetails" roleURI="http://www.deitaxonomy.com/role/DisclosureGoodwillAndOtherIntangibleAssetsDetails" />
  <link:roleRef xlink:type="simple" xlink:href="verx-20260630.xsd#DisclosureDebtIndebtednessDetails" roleURI="http://www.deitaxonomy.com/role/DisclosureDebtIndebtednessDetails" />
  <link:roleRef xlink:type="simple" xlink:href="verx-20260630.xsd#DisclosureDebtInterestExpenseRelatedToNotesDetails" roleURI="http://www.deitaxonomy.com/role/DisclosureDebtInterestExpenseRelatedToNotesDetails" />
  <link:roleRef xlink:type="simple" xlink:href="verx-20260630.xsd#DisclosureSegmentDisclosuresSegmentIncomeDetails" roleURI="http://www.deitaxonomy.com/role/DisclosureSegmentDisclosuresSegmentIncomeDetails" />
  <link:arcroleRef arcroleURI="https://xbrl.org/2023/arcrole/summation-item" xlink:type="simple" xlink:href="https://www.xbrl.org/2023/calculation-1.1.xsd#summation-item" />
  <link:calculationLink xlink:role="http://www.deitaxonomy.com/role/StatementCondensedConsolidatedBalanceSheets" xlink:type="extended" xlink:title="995200100 - Statement - Condensed Consolidated Balance Sheets">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets" xlink:label="us-gaap_Assets" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent" xlink:label="us-gaap_AssetsCurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_AssetsCurrent_639214587748469559" order="1" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="us-gaap_AccountsReceivableNetCurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_639214587748469559" xlink:to="us-gaap_AccountsReceivableNetCurrent_639214587748469559" order="1" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_639214587748469559" xlink:to="us-gaap_CashAndCashEquivalentsAtCarryingValue_639214587748469559" order="2" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_639214587748469559" xlink:to="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_639214587748469559" order="3" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue" xlink:label="us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_639214587748469559" xlink:to="us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue_639214587748469559" order="4" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermInvestments" xlink:label="us-gaap_LongTermInvestments_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_LongTermInvestments_639214587748469559" order="2" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="us-gaap_OtherAssetsNoncurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_OtherAssetsNoncurrent_639214587748469559" order="3" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedComputerSoftwareNet" xlink:label="us-gaap_CapitalizedComputerSoftwareNet_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_CapitalizedComputerSoftwareNet_639214587748469559" order="4" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostNetNoncurrent" xlink:label="us-gaap_CapitalizedContractCostNetNoncurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_CapitalizedContractCostNetNoncurrent_639214587748469559" order="5" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_OperatingLeaseRightOfUseAsset_639214587748469559" order="6" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxAssetsNet" xlink:label="us-gaap_DeferredIncomeTaxAssetsNet_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_DeferredIncomeTaxAssetsNet_639214587748469559" order="7" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization" xlink:label="us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_639214587748469559" order="8" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_GoodwillAndIntangibleAssetExcludingCapitalizedCostSoftwareToBeSoldLeasedOrMarketedAfterAccumulatedAmortization" xlink:label="verx_GoodwillAndIntangibleAssetExcludingCapitalizedCostSoftwareToBeSoldLeasedOrMarketedAfterAccumulatedAmortization_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="verx_GoodwillAndIntangibleAssetExcludingCapitalizedCostSoftwareToBeSoldLeasedOrMarketedAfterAccumulatedAmortization_639214587748469559" order="9" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommitmentsAndContingencies" xlink:label="us-gaap_CommitmentsAndContingencies_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesAndStockholdersEquity" xlink:to="us-gaap_CommitmentsAndContingencies_639214587748469559" order="1" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities" xlink:label="us-gaap_Liabilities_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesAndStockholdersEquity" xlink:to="us-gaap_Liabilities_639214587748469559" order="2" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639214587748469559" xlink:to="us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent_639214587748469559" order="1" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxLiabilitiesNet" xlink:label="us-gaap_DeferredIncomeTaxLiabilitiesNet_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639214587748469559" xlink:to="us-gaap_DeferredIncomeTaxLiabilitiesNet_639214587748469559" order="2" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerLiabilityNoncurrent" xlink:label="us-gaap_ContractWithCustomerLiabilityNoncurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639214587748469559" xlink:to="us-gaap_ContractWithCustomerLiabilityNoncurrent_639214587748469559" order="3" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639214587748469559" xlink:to="us-gaap_OperatingLeaseLiabilityNoncurrent_639214587748469559" order="4" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="us-gaap_LongTermDebtNoncurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639214587748469559" xlink:to="us-gaap_LongTermDebtNoncurrent_639214587748469559" order="5" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiabilityNoncurrent" xlink:label="us-gaap_FinanceLeaseLiabilityNoncurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639214587748469559" xlink:to="us-gaap_FinanceLeaseLiabilityNoncurrent_639214587748469559" order="6" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_DeferredOtherLiabilitiesCurrent" xlink:label="verx_DeferredOtherLiabilitiesCurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639214587748469559" xlink:to="verx_DeferredOtherLiabilitiesCurrent_639214587748469559" order="7" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent" xlink:label="us-gaap_LiabilitiesCurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639214587748469559" xlink:to="us-gaap_LiabilitiesCurrent_639214587748469559" order="8" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableCurrent" xlink:label="us-gaap_AccountsPayableCurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639214587748469559" xlink:to="us-gaap_AccountsPayableCurrent_639214587748469559" order="1" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_AccruedVariableCompensationCurrent" xlink:label="verx_AccruedVariableCompensationCurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639214587748469559" xlink:to="verx_AccruedVariableCompensationCurrent_639214587748469559" order="2" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesCurrent" xlink:label="us-gaap_AccruedLiabilitiesCurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639214587748469559" xlink:to="us-gaap_AccruedLiabilitiesCurrent_639214587748469559" order="3" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerLiabilityCurrent" xlink:label="us-gaap_ContractWithCustomerLiabilityCurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639214587748469559" xlink:to="us-gaap_ContractWithCustomerLiabilityCurrent_639214587748469559" order="4" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityCurrent" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639214587748469559" xlink:to="us-gaap_OperatingLeaseLiabilityCurrent_639214587748469559" order="5" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiabilityCurrent" xlink:label="us-gaap_FinanceLeaseLiabilityCurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639214587748469559" xlink:to="us-gaap_FinanceLeaseLiabilityCurrent_639214587748469559" order="6" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationContingentConsiderationLiabilityCurrent" xlink:label="us-gaap_BusinessCombinationContingentConsiderationLiabilityCurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639214587748469559" xlink:to="us-gaap_BusinessCombinationContingentConsiderationLiabilityCurrent_639214587748469559" order="7" use="optional" weight="1" priority="3" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_CustomerFundsObligationsCurrent" xlink:label="verx_CustomerFundsObligationsCurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639214587748469559" xlink:to="verx_CustomerFundsObligationsCurrent_639214587748469559" order="8" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeRelatedLiabilitiesCurrent" xlink:label="us-gaap_EmployeeRelatedLiabilitiesCurrent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639214587748469559" xlink:to="us-gaap_EmployeeRelatedLiabilitiesCurrent_639214587748469559" order="9" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity" xlink:label="us-gaap_StockholdersEquity_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesAndStockholdersEquity" xlink:to="us-gaap_StockholdersEquity_639214587748469559" order="3" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_639214587748469559" xlink:to="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_639214587748469559" order="1" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockValue" xlink:label="us-gaap_PreferredStockValue_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_639214587748469559" xlink:to="us-gaap_PreferredStockValue_639214587748469559" order="2" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockValue" xlink:label="us-gaap_CommonStockValue_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_639214587748469559" xlink:to="us-gaap_CommonStockValue_639214587748469559" order="3" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockCommonValue" xlink:label="us-gaap_TreasuryStockCommonValue_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_639214587748469559" xlink:to="us-gaap_TreasuryStockCommonValue_639214587748469559" order="4" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="us-gaap_AdditionalPaidInCapital_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_639214587748469559" xlink:to="us-gaap_AdditionalPaidInCapital_639214587748469559" order="5" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_639214587748469559" xlink:to="us-gaap_RetainedEarningsAccumulatedDeficit_639214587748469559" order="6" use="optional" weight="1" priority="2" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.deitaxonomy.com/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncomeLoss" xlink:type="extended" xlink:title="995200200 - Statement - Condensed Consolidated Statements of Comprehensive Income (Loss)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTax" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_ComprehensiveIncomeNetOfTax" xlink:to="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_639214587748469559" order="1" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent" xlink:label="us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_639214587748469559" xlink:to="us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent_639214587748469559" order="1" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent" xlink:label="us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_639214587748469559" xlink:to="us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_639214587748469559" order="2" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss" xlink:label="us-gaap_NetIncomeLoss_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_ComprehensiveIncomeNetOfTax" xlink:to="us-gaap_NetIncomeLoss_639214587748469559" order="2" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="us-gaap_IncomeTaxExpenseBenefit_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss_639214587748469559" xlink:to="us-gaap_IncomeTaxExpenseBenefit_639214587748469559" order="1" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss_639214587748469559" xlink:to="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_639214587748469559" order="2" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestIncomeExpenseNonoperatingNet" xlink:label="us-gaap_InterestIncomeExpenseNonoperatingNet_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_639214587748469559" xlink:to="us-gaap_InterestIncomeExpenseNonoperatingNet_639214587748469559" order="1" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss" xlink:label="us-gaap_OperatingIncomeLoss_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_639214587748469559" xlink:to="us-gaap_OperatingIncomeLoss_639214587748469559" order="2" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingExpenses" xlink:label="us-gaap_OperatingExpenses_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingIncomeLoss_639214587748469559" xlink:to="us-gaap_OperatingExpenses_639214587748469559" order="1" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNonrecurringIncomeExpense" xlink:label="us-gaap_OtherNonrecurringIncomeExpense_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingExpenses_639214587748469559" xlink:to="us-gaap_OtherNonrecurringIncomeExpense_639214587748469559" order="1" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_ChangeInSettlementValueOfAcquisitionRelatedLiability" xlink:label="verx_ChangeInSettlementValueOfAcquisitionRelatedLiability_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingExpenses_639214587748469559" xlink:to="verx_ChangeInSettlementValueOfAcquisitionRelatedLiability_639214587748469559" order="2" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherDepreciationAndAmortization" xlink:label="us-gaap_OtherDepreciationAndAmortization_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingExpenses_639214587748469559" xlink:to="us-gaap_OtherDepreciationAndAmortization_639214587748469559" order="3" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeneralAndAdministrativeExpense" xlink:label="us-gaap_GeneralAndAdministrativeExpense_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingExpenses_639214587748469559" xlink:to="us-gaap_GeneralAndAdministrativeExpense_639214587748469559" order="4" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SellingAndMarketingExpense" xlink:label="us-gaap_SellingAndMarketingExpense_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingExpenses_639214587748469559" xlink:to="us-gaap_SellingAndMarketingExpense_639214587748469559" order="5" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="us-gaap_ResearchAndDevelopmentExpense_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingExpenses_639214587748469559" xlink:to="us-gaap_ResearchAndDevelopmentExpense_639214587748469559" order="6" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GrossProfit" xlink:label="us-gaap_GrossProfit_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingIncomeLoss_639214587748469559" xlink:to="us-gaap_GrossProfit_639214587748469559" order="2" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServicesSold" xlink:label="us-gaap_CostOfGoodsAndServicesSold_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_GrossProfit_639214587748469559" xlink:to="us-gaap_CostOfGoodsAndServicesSold_639214587748469559" order="1" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_GrossProfit_639214587748469559" xlink:to="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_639214587748469559" order="2" use="optional" weight="1" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.deitaxonomy.com/role/StatementCondensedConsolidatedStatementsOfCashFlows" xlink:type="extended" xlink:title="995200400 - Statement - Condensed Consolidated Statements of Cash Flows">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_637339730280317166" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_637339730280317166" xlink:to="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_639214587748469559" order="1" use="optional" weight="1" priority="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_637339730280317166" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" order="2" use="optional" weight="1" priority="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss" xlink:label="us-gaap_ProfitLoss_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="us-gaap_ProfitLoss_639214587748469559" order="1" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_IncreaseDecreaseInOtherOperatingCapital" xlink:label="verx_IncreaseDecreaseInOtherOperatingCapital_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="verx_IncreaseDecreaseInOtherOperatingCapital_639214587748469559" order="2" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HostingArrangementServiceContractImplementationCostExpenseAmortization" xlink:label="us-gaap_HostingArrangementServiceContractImplementationCostExpenseAmortization_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="us-gaap_HostingArrangementServiceContractImplementationCostExpenseAmortization_639214587748469559" order="3" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="us-gaap_AmortizationOfFinancingCosts_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="us-gaap_AmortizationOfFinancingCosts_639214587748469559" order="4" use="optional" weight="1" priority="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepreciationAndAmortization" xlink:label="us-gaap_DepreciationAndAmortization_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="us-gaap_DepreciationAndAmortization_639214587748469559" order="5" use="optional" weight="1" priority="1" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_BusinessCombinationContingentConsiderationArrangementsChangeInFairValueOfContingentConsiderationLiabilities" xlink:label="verx_BusinessCombinationContingentConsiderationArrangementsChangeInFairValueOfContingentConsiderationLiabilities_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="verx_BusinessCombinationContingentConsiderationArrangementsChangeInFairValueOfContingentConsiderationLiabilities_639214587748469559" order="6" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsPayable" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="us-gaap_IncreaseDecreaseInAccountsPayable_639214587748469559" order="7" use="optional" weight="1" priority="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:label="us-gaap_IncreaseDecreaseInAccountsReceivable_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="us-gaap_IncreaseDecreaseInAccountsReceivable_639214587748469559" order="8" use="optional" weight="-1" priority="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOtherCurrentLiabilities" xlink:label="us-gaap_IncreaseDecreaseInOtherCurrentLiabilities_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="us-gaap_IncreaseDecreaseInOtherCurrentLiabilities_639214587748469559" order="9" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_639214587748469559" order="10" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_IncreaseDecreaseInPaymentsForPurchaseCommitmentAndContingentConsiderationLiabilitiesInExcessOfInitialFairValue" xlink:label="verx_IncreaseDecreaseInPaymentsForPurchaseCommitmentAndContingentConsiderationLiabilitiesInExcessOfInitialFairValue_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="verx_IncreaseDecreaseInPaymentsForPurchaseCommitmentAndContingentConsiderationLiabilitiesInExcessOfInitialFairValue_639214587748469559" order="11" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccruedLiabilities" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilities_639214587748469559" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="us-gaap_IncreaseDecreaseInAccruedLiabilities_639214587748469559" order="12" use="optional" weight="1" priority="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInContractWithCustomerLiability" xlink:label="us-gaap_IncreaseDecreaseInContractWithCustomerLiability_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="us-gaap_IncreaseDecreaseInContractWithCustomerLiability_639214587748604727" order="13" use="optional" weight="1" priority="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInDeferredCompensation" xlink:label="us-gaap_IncreaseDecreaseInDeferredCompensation_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="us-gaap_IncreaseDecreaseInDeferredCompensation_639214587748604727" order="14" use="optional" weight="1" priority="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="us-gaap_DeferredIncomeTaxExpenseBenefit_639214587748604727" order="15" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_639214587748604727" order="16" use="optional" weight="-1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_IncreaseDecreaseInCapitalizedContractCostNetNonCurrent" xlink:label="verx_IncreaseDecreaseInCapitalizedContractCostNetNonCurrent_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="verx_IncreaseDecreaseInCapitalizedContractCostNetNonCurrent_639214587748604727" order="17" use="optional" weight="-1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNoncashIncomeExpense" xlink:label="us-gaap_OtherNoncashIncomeExpense_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="us-gaap_OtherNoncashIncomeExpense_639214587748604727" order="18" use="optional" weight="-1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProvisionForOtherLosses" xlink:label="us-gaap_ProvisionForOtherLosses_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="us-gaap_ProvisionForOtherLosses_639214587748604727" order="19" use="optional" weight="1" priority="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensation" xlink:label="us-gaap_ShareBasedCompensation_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639214587748469559" xlink:to="us-gaap_ShareBasedCompensation_639214587748604727" order="20" use="optional" weight="1" priority="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_637339730280317166" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivities_639214587748604727" order="3" use="optional" weight="1" priority="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquireProductiveAssets" xlink:label="us-gaap_PaymentsToAcquireProductiveAssets_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_639214587748604727" xlink:to="us-gaap_PaymentsToAcquireProductiveAssets_639214587748604727" order="1" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquireLongtermInvestments" xlink:label="us-gaap_PaymentsToAcquireLongtermInvestments_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_639214587748604727" xlink:to="us-gaap_PaymentsToAcquireLongtermInvestments_639214587748604727" order="2" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_PropertyAndEquipmentAdditions" xlink:label="verx_PropertyAndEquipmentAdditions_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_639214587748604727" xlink:to="verx_PropertyAndEquipmentAdditions_639214587748604727" order="3" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_CapitalizedSoftwareAdditions" xlink:label="verx_CapitalizedSoftwareAdditions_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_639214587748604727" xlink:to="verx_CapitalizedSoftwareAdditions_639214587748604727" order="4" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt" xlink:label="us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_639214587748604727" xlink:to="us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_639214587748604727" order="5" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities" xlink:label="us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_639214587748604727" xlink:to="us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities_639214587748604727" order="6" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_637339730280317166" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivities_639214587748604727" order="4" use="optional" weight="1" priority="1" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_IncreaseDecreaseInCustomerFundsObligations" xlink:label="verx_IncreaseDecreaseInCustomerFundsObligations_639214587748604727" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639214587748604727" xlink:to="verx_IncreaseDecreaseInCustomerFundsObligations_639214587748604727" order="1" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeasePrincipalPayments" xlink:label="us-gaap_FinanceLeasePrincipalPayments_639214587748625172" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639214587748604727" xlink:to="us-gaap_FinanceLeasePrincipalPayments_639214587748625172" order="2" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentForContingentConsiderationLiabilityFinancingActivities" xlink:label="us-gaap_PaymentForContingentConsiderationLiabilityFinancingActivities_639214587748626473" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639214587748604727" xlink:to="us-gaap_PaymentForContingentConsiderationLiabilityFinancingActivities_639214587748626473" order="3" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_ProceedsFromPurchasesOfStockUnderEspp" xlink:label="verx_ProceedsFromPurchasesOfStockUnderEspp_639214587748626473" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639214587748604727" xlink:to="verx_ProceedsFromPurchasesOfStockUnderEspp_639214587748626473" order="4" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock" xlink:label="us-gaap_PaymentsForRepurchaseOfCommonStock_639214587748626473" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639214587748604727" xlink:to="us-gaap_PaymentsForRepurchaseOfCommonStock_639214587748626473" order="5" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation" xlink:label="us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_639214587748626473" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639214587748604727" xlink:to="us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_639214587748626473" order="6" use="optional" weight="-1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromStockOptionsExercised" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639214587748604727" xlink:to="us-gaap_ProceedsFromStockOptionsExercised_639214587748631865" order="7" use="optional" weight="1" priority="3" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.deitaxonomy.com/role/StatementCondensedConsolidatedStatementsOfCashFlowsParenthetical" xlink:type="extended" xlink:title="995200405 - Statement - Condensed Consolidated Statements of Cash Flows (Parenthetical)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:to="us-gaap_CashAndCashEquivalentsAtCarryingValue_639214587748631865" order="1" use="optional" weight="1" priority="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndSecuritiesSegregatedUnderFederalAndOtherRegulations" xlink:label="us-gaap_CashAndSecuritiesSegregatedUnderFederalAndOtherRegulations_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:to="us-gaap_CashAndSecuritiesSegregatedUnderFederalAndOtherRegulations_639214587748631865" order="2" use="optional" weight="1" priority="2" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.deitaxonomy.com/role/DisclosureSummaryOfSignificantAccountingPoliciesSupplementalBalanceSheetDisclosuresDetails" xlink:type="extended" xlink:title="99940101 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Supplemental Balance Sheet Disclosures (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesCurrent" xlink:label="us-gaap_AccruedLiabilitiesCurrent" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAccruedLiabilitiesCurrent" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AccruedLiabilitiesCurrent" xlink:to="us-gaap_OtherAccruedLiabilitiesCurrent_639214587748631865" order="1" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxesPayableCurrent" xlink:label="us-gaap_TaxesPayableCurrent_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AccruedLiabilitiesCurrent" xlink:to="us-gaap_TaxesPayableCurrent_639214587748631865" order="2" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedProfessionalFeesCurrent" xlink:label="us-gaap_AccruedProfessionalFeesCurrent_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AccruedLiabilitiesCurrent" xlink:to="us-gaap_AccruedProfessionalFeesCurrent_639214587748631865" order="3" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="us-gaap_OtherAssetsNoncurrent" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_UnamortizedCloudComputingImplementationCostsNonCurrent" xlink:label="verx_UnamortizedCloudComputingImplementationCostsNonCurrent_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OtherAssetsNoncurrent" xlink:to="verx_UnamortizedCloudComputingImplementationCostsNonCurrent_639214587748631865" order="1" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsMiscellaneousNoncurrent" xlink:label="us-gaap_OtherAssetsMiscellaneousNoncurrent_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OtherAssetsNoncurrent" xlink:to="us-gaap_OtherAssetsMiscellaneousNoncurrent_639214587748631865" order="2" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepaidExpenseCurrent" xlink:label="us-gaap_PrepaidExpenseCurrent_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:to="us-gaap_PrepaidExpenseCurrent_639214587748631865" order="1" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_UnamortizedCloudComputingImplementationCostsPrepaidExpenseCurrent" xlink:label="verx_UnamortizedCloudComputingImplementationCostsPrepaidExpenseCurrent_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:to="verx_UnamortizedCloudComputingImplementationCostsPrepaidExpenseCurrent_639214587748631865" order="2" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepaidInsurance" xlink:label="us-gaap_PrepaidInsurance_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:to="us-gaap_PrepaidInsurance_639214587748631865" order="3" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_PrepaidLicensesAndSupportCurrent" xlink:label="verx_PrepaidLicensesAndSupportCurrent_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:to="verx_PrepaidLicensesAndSupportCurrent_639214587748631865" order="4" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepaidTaxes" xlink:label="us-gaap_PrepaidTaxes_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:to="us-gaap_PrepaidTaxes_639214587748631865" order="5" use="optional" weight="1" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.deitaxonomy.com/role/DisclosureAcquisitionsFairValueOfAssetsAcquiredAndLiabilitiesAssumedDetails" xlink:type="extended" xlink:title="99940302 - Disclosure - ACQUISITIONS - Fair value of assets acquired and liabilities assumed (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther_639214587748631865" order="1" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities_639214587748631865" order="2" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_639214587748631865" order="3" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Goodwill" xlink:label="us-gaap_Goodwill_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:to="us-gaap_Goodwill_639214587748631865" order="4" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_639214587748631865" order="5" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_639214587748631865" order="6" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_639214587748631865" order="7" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_639214587748631865" order="8" use="optional" weight="1" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.deitaxonomy.com/role/DisclosurePropertyAndEquipmentDetails" xlink:type="extended" xlink:title="99940501 - Disclosure - PROPERTY AND EQUIPMENT (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization" xlink:label="us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization" xlink:label="us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_1" xlink:to="us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization_639214587748631865" order="1" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization" xlink:label="us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_1" xlink:to="us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization_639214587748631865" order="2" use="optional" weight="1" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.deitaxonomy.com/role/DisclosurePropertyAndEquipmentMajorComponentsOfInternalUseSoftwareDetails" xlink:type="extended" xlink:title="99940503 - Disclosure - PROPERTY AND EQUIPMENT - Major components of internal-use software (Details)">
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_PropertyPlantAndEquipmentNetExcludingInProcessInternalUseSoftware" xlink:label="verx_PropertyPlantAndEquipmentNetExcludingInProcessInternalUseSoftware" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_PropertyPlantAndEquipmentNetExcludingInProcessInternalUseSoftware" xlink:to="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_639214587748631865" order="1" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentGross" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_PropertyPlantAndEquipmentNetExcludingInProcessInternalUseSoftware" xlink:to="us-gaap_PropertyPlantAndEquipmentGross_639214587748631865" order="2" use="optional" weight="1" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.deitaxonomy.com/role/DisclosureCapitalizedSoftwareDetails" xlink:type="extended" xlink:title="99940601 - Disclosure - CAPITALIZED SOFTWARE (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedComputerSoftwareNet" xlink:label="us-gaap_CapitalizedComputerSoftwareNet" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_InProcessCapitalizedSoftware" xlink:label="verx_InProcessCapitalizedSoftware_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CapitalizedComputerSoftwareNet" xlink:to="verx_InProcessCapitalizedSoftware_639214587748631865" order="1" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_CapitalizedComputerSoftwareExcludingInProcessSoftware" xlink:label="verx_CapitalizedComputerSoftwareExcludingInProcessSoftware_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CapitalizedComputerSoftwareNet" xlink:to="verx_CapitalizedComputerSoftwareExcludingInProcessSoftware_639214587748631865" order="2" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedComputerSoftwareAccumulatedAmortization" xlink:label="us-gaap_CapitalizedComputerSoftwareAccumulatedAmortization_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_CapitalizedComputerSoftwareExcludingInProcessSoftware_639214587748631865" xlink:to="us-gaap_CapitalizedComputerSoftwareAccumulatedAmortization_639214587748631865" order="1" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedComputerSoftwareGross" xlink:label="us-gaap_CapitalizedComputerSoftwareGross_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_CapitalizedComputerSoftwareExcludingInProcessSoftware_639214587748631865" xlink:to="us-gaap_CapitalizedComputerSoftwareGross_639214587748631865" order="2" use="optional" weight="1" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.deitaxonomy.com/role/DisclosureGoodwillAndOtherIntangibleAssetsDetails" xlink:type="extended" xlink:title="99940701 - Disclosure - GOODWILL AND OTHER INTANGIBLE ASSETS (Details)">
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_GoodwillAndIntangibleAssetExcludingCapitalizedCostSoftwareToBeSoldLeasedOrMarketedAfterAccumulatedAmortization" xlink:label="verx_GoodwillAndIntangibleAssetExcludingCapitalizedCostSoftwareToBeSoldLeasedOrMarketedAfterAccumulatedAmortization_1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Goodwill" xlink:label="us-gaap_Goodwill_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_GoodwillAndIntangibleAssetExcludingCapitalizedCostSoftwareToBeSoldLeasedOrMarketedAfterAccumulatedAmortization_1" xlink:to="us-gaap_Goodwill_639214587748631865" order="1" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsNet" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_GoodwillAndIntangibleAssetExcludingCapitalizedCostSoftwareToBeSoldLeasedOrMarketedAfterAccumulatedAmortization_1" xlink:to="us-gaap_FiniteLivedIntangibleAssetsNet_639214587748631865" order="2" use="optional" weight="1" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.deitaxonomy.com/role/DisclosureDebtIndebtednessDetails" xlink:type="extended" xlink:title="99940802 - Disclosure - DEBT - Indebtedness (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebt" xlink:label="us-gaap_LongTermDebt" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LongTermDebt" xlink:to="us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_639214587748631865" order="1" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentCarryingAmount" xlink:label="us-gaap_DebtInstrumentCarryingAmount_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LongTermDebt" xlink:to="us-gaap_DebtInstrumentCarryingAmount_639214587748631865" order="2" use="optional" weight="1" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.deitaxonomy.com/role/DisclosureDebtInterestExpenseRelatedToNotesDetails" xlink:type="extended" xlink:title="99940803 - Disclosure - DEBT - Interest expense related to Notes (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseDebt" xlink:label="us-gaap_InterestExpenseDebt_1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseDebtExcludingAmortization" xlink:label="us-gaap_InterestExpenseDebtExcludingAmortization_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_InterestExpenseDebt_1" xlink:to="us-gaap_InterestExpenseDebtExcludingAmortization_639214587748631865" order="1" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="us-gaap_AmortizationOfFinancingCosts_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_InterestExpenseDebt_1" xlink:to="us-gaap_AmortizationOfFinancingCosts_639214587748631865" order="2" use="optional" weight="1" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.deitaxonomy.com/role/DisclosureSegmentDisclosuresSegmentIncomeDetails" xlink:type="extended" xlink:title="99941302 - Disclosure - SEGMENT DISCLOSURES - Segment income (Details)">
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization" xlink:label="verx_AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization_1" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_TransactionCosts" xlink:label="verx_TransactionCosts_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization_1" xlink:to="verx_TransactionCosts_639214587748631865" order="1" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_ShareBasedPaymentArrangementAdditionalExpenseForAcquisition" xlink:label="verx_ShareBasedPaymentArrangementAdditionalExpenseForAcquisition_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization_1" xlink:to="verx_ShareBasedPaymentArrangementAdditionalExpenseForAcquisition_639214587748631865" order="2" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_ChangeInFairValueOfAcquisitionContingentEarnOuts" xlink:label="verx_ChangeInFairValueOfAcquisitionContingentEarnOuts_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization_1" xlink:to="verx_ChangeInFairValueOfAcquisitionContingentEarnOuts_639214587748631865" order="3" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsideration" xlink:label="verx_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsideration_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization_1" xlink:to="verx_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsideration_639214587748631865" order="4" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeveranceCosts1" xlink:label="us-gaap_SeveranceCosts1_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization_1" xlink:to="us-gaap_SeveranceCosts1_639214587748631865" order="5" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensation" xlink:label="us-gaap_ShareBasedCompensation_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization_1" xlink:to="us-gaap_ShareBasedCompensation_639214587748631865" order="6" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HostingArrangementServiceContractImplementationCostExpenseAmortization" xlink:label="us-gaap_HostingArrangementServiceContractImplementationCostExpenseAmortization_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization_1" xlink:to="us-gaap_HostingArrangementServiceContractImplementationCostExpenseAmortization_639214587748631865" order="7" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_AmortizationOfAcquiredIntangibleAssets" xlink:label="verx_AmortizationOfAcquiredIntangibleAssets_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization_1" xlink:to="verx_AmortizationOfAcquiredIntangibleAssets_639214587748631865" order="8" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="verx-20260630.xsd#verx_DepreciationAndAmortizationOfCapitalizedSoftwareAndAcquiredIntangibleAssets" xlink:label="verx_DepreciationAndAmortizationOfCapitalizedSoftwareAndAcquiredIntangibleAssets_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization_1" xlink:to="verx_DepreciationAndAmortizationOfCapitalizedSoftwareAndAcquiredIntangibleAssets_639214587748631865" order="9" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherDepreciationAndAmortization" xlink:label="us-gaap_OtherDepreciationAndAmortization_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization_1" xlink:to="us-gaap_OtherDepreciationAndAmortization_639214587748631865" order="10" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="us-gaap_IncomeTaxExpenseBenefit_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization_1" xlink:to="us-gaap_IncomeTaxExpenseBenefit_639214587748631865" order="11" use="optional" weight="-1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestIncomeExpenseNet" xlink:label="us-gaap_InterestIncomeExpenseNet_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization_1" xlink:to="us-gaap_InterestIncomeExpenseNet_639214587748631865" order="12" use="optional" weight="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss" xlink:label="us-gaap_NetIncomeLoss_639214587748631865" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="verx_AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization_1" xlink:to="us-gaap_NetIncomeLoss_639214587748631865" order="13" use="optional" weight="1" />
  </link:calculationLink>
</link:linkbase>
