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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2025 Workiva-->
<!--r:0235df8a-417f-4a17-a4c7-39f65d82ba93,g:b2a0abcc-ad0b-4df5-bf7b-c5020d6b6619-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" 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">
  <link:roleRef roleURI="http://cassinfo.com/role/CONSOLIDATEDBALANCESHEETS" xlink:type="simple" xlink:href="cass-20241231.xsd#CONSOLIDATEDBALANCESHEETS"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/CONSOLIDATEDBALANCESHEETS" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Deposits_5400c23e-9bbf-4541-a348-8a7dc5ae059a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Deposits"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestBearingDepositLiabilities_8c92fe08-d19f-44a6-84ab-f381f6de571b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestBearingDepositLiabilities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Deposits_5400c23e-9bbf-4541-a348-8a7dc5ae059a" xlink:to="loc_us-gaap_NoninterestBearingDepositLiabilities_8c92fe08-d19f-44a6-84ab-f381f6de571b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestBearingDepositLiabilities_ddad9b0e-1e89-400b-9e11-5cbfad4ea942" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestBearingDepositLiabilities"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Deposits_5400c23e-9bbf-4541-a348-8a7dc5ae059a" xlink:to="loc_us-gaap_InterestBearingDepositLiabilities_ddad9b0e-1e89-400b-9e11-5cbfad4ea942" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsAndShortTermInvestments_d7e7ffe1-e3c7-46cb-81c0-b96a4c630b83" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashCashEquivalentsAndShortTermInvestments"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndDueFromBanks_e34a088a-e2ce-46f5-8b70-bf116ac2c872" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashAndDueFromBanks"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsAndShortTermInvestments_d7e7ffe1-e3c7-46cb-81c0-b96a4c630b83" xlink:to="loc_us-gaap_CashAndDueFromBanks_e34a088a-e2ce-46f5-8b70-bf116ac2c872" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermInvestments_6e29215e-2244-4964-a39e-c4dd1ddca0ea" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShortTermInvestments"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsAndShortTermInvestments_d7e7ffe1-e3c7-46cb-81c0-b96a4c630b83" xlink:to="loc_us-gaap_ShortTermInvestments_6e29215e-2244-4964-a39e-c4dd1ddca0ea" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_d2774201-152b-45e6-97d4-6e5ff8a1504e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Assets"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssets_804259af-e137-4a24-b160-603d9b3a9b27" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherAssets"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_d2774201-152b-45e6-97d4-6e5ff8a1504e" xlink:to="loc_us-gaap_OtherAssets_804259af-e137-4a24-b160-603d9b3a9b27" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_5bc42d20-2273-4545-93e9-a3e18e171f23" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_d2774201-152b-45e6-97d4-6e5ff8a1504e" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_5bc42d20-2273-4545-93e9-a3e18e171f23" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_72f4b8cf-6a62-42d8-8ccb-ffcdeb9d2bba" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Goodwill"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_d2774201-152b-45e6-97d4-6e5ff8a1504e" xlink:to="loc_us-gaap_Goodwill_72f4b8cf-6a62-42d8-8ccb-ffcdeb9d2bba" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsAndShortTermInvestments_587a6e98-66d2-4d08-85e5-952e635d5d88" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashCashEquivalentsAndShortTermInvestments"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_d2774201-152b-45e6-97d4-6e5ff8a1504e" xlink:to="loc_us-gaap_CashCashEquivalentsAndShortTermInvestments_587a6e98-66d2-4d08-85e5-952e635d5d88" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_PaymentsInAdvanceOfFunding_02d0a806-c933-43b9-b000-558ac82b4b6b" xlink:href="cass-20241231.xsd#cass_PaymentsInAdvanceOfFunding"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_d2774201-152b-45e6-97d4-6e5ff8a1504e" xlink:to="loc_cass_PaymentsInAdvanceOfFunding_02d0a806-c933-43b9-b000-558ac82b4b6b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_797e33ca-3718-45be-99da-88af6d11771c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_d2774201-152b-45e6-97d4-6e5ff8a1504e" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_797e33ca-3718-45be-99da-88af6d11771c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_9403b2cd-c3b5-48f2-bd8e-02ad1b881f9f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_d2774201-152b-45e6-97d4-6e5ff8a1504e" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_9403b2cd-c3b5-48f2-bd8e-02ad1b881f9f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BankOwnedLifeInsurance_8aa2cbb4-2347-4d1c-aa44-5932a0cf45d5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BankOwnedLifeInsurance"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_d2774201-152b-45e6-97d4-6e5ff8a1504e" xlink:to="loc_us-gaap_BankOwnedLifeInsurance_8aa2cbb4-2347-4d1c-aa44-5932a0cf45d5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReceivablesFromCustomers_b8fde285-b6e9-4332-83ba-912b8e224770" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReceivablesFromCustomers"/>
    <link:calculationArc order="9" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_d2774201-152b-45e6-97d4-6e5ff8a1504e" xlink:to="loc_us-gaap_ReceivablesFromCustomers_b8fde285-b6e9-4332-83ba-912b8e224770" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_a3cf64f3-d759-4316-b560-6460fee10869" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill"/>
    <link:calculationArc order="10" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_d2774201-152b-45e6-97d4-6e5ff8a1504e" xlink:to="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_a3cf64f3-d759-4316-b560-6460fee10869" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_1c0001eb-e915-447b-bf84-80ebc596a51d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockValue_a018b883-4c41-44b7-b193-7f5ed893cf02" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PreferredStockValue"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_1c0001eb-e915-447b-bf84-80ebc596a51d" xlink:to="loc_us-gaap_PreferredStockValue_a018b883-4c41-44b7-b193-7f5ed893cf02" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockValueOutstanding_a2cc6453-4cc7-4d1d-bb13-0724e4bdea64" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockValueOutstanding"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_1c0001eb-e915-447b-bf84-80ebc596a51d" xlink:to="loc_us-gaap_CommonStockValueOutstanding_a2cc6453-4cc7-4d1d-bb13-0724e4bdea64" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalCommonStock_a088de56-5c1c-46e8-a62d-edd52c079473" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AdditionalPaidInCapitalCommonStock"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_1c0001eb-e915-447b-bf84-80ebc596a51d" xlink:to="loc_us-gaap_AdditionalPaidInCapitalCommonStock_a088de56-5c1c-46e8-a62d-edd52c079473" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_09f70e78-adb3-47c8-b6ca-6c22667038bc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_1c0001eb-e915-447b-bf84-80ebc596a51d" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_09f70e78-adb3-47c8-b6ca-6c22667038bc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValue_4466630f-4131-4791-bf7c-aecd50b642c1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockValue"/>
    <link:calculationArc order="5" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_1c0001eb-e915-447b-bf84-80ebc596a51d" xlink:to="loc_us-gaap_TreasuryStockValue_4466630f-4131-4791-bf7c-aecd50b642c1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_a2628c9b-410d-4e75-b2cf-cad434d845bc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_1c0001eb-e915-447b-bf84-80ebc596a51d" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_a2628c9b-410d-4e75-b2cf-cad434d845bc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_d6e936f0-78e6-4c77-8e62-43a4c3b5d321" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_62e872b4-c5c6-4d15-86aa-2f98d573b90d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_d6e936f0-78e6-4c77-8e62-43a4c3b5d321" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_62e872b4-c5c6-4d15-86aa-2f98d573b90d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_ced9899a-0d97-4c50-9bef-10281751c43a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_d6e936f0-78e6-4c77-8e62-43a4c3b5d321" xlink:to="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_ced9899a-0d97-4c50-9bef-10281751c43a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_cef6d93d-0ee8-4310-970d-307c364660f6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_893d0d71-3f66-44e7-91da-ed767667a4ec" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Liabilities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_cef6d93d-0ee8-4310-970d-307c364660f6" xlink:to="loc_us-gaap_Liabilities_893d0d71-3f66-44e7-91da-ed767667a4ec" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_7303f149-2bfd-4750-be7c-fd38e5d277f2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockholdersEquity"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_cef6d93d-0ee8-4310-970d-307c364660f6" xlink:to="loc_us-gaap_StockholdersEquity_7303f149-2bfd-4750-be7c-fd38e5d277f2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_cd92627a-948a-49e0-99c2-f9dda3006629" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Liabilities"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_AccountsAndDraftsPayableCarryingAmount_cf71cbee-2318-4bc9-a1b3-9e3184d0d0ef" xlink:href="cass-20241231.xsd#cass_AccountsAndDraftsPayableCarryingAmount"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_cd92627a-948a-49e0-99c2-f9dda3006629" xlink:to="loc_cass_AccountsAndDraftsPayableCarryingAmount_cf71cbee-2318-4bc9-a1b3-9e3184d0d0ef" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Deposits_871267d0-3292-4be2-af36-6b45232d3a5b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Deposits"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_cd92627a-948a-49e0-99c2-f9dda3006629" xlink:to="loc_us-gaap_Deposits_871267d0-3292-4be2-af36-6b45232d3a5b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilities_e3efa13a-1c8c-41d0-b3fa-d94fd9b203ba" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherLiabilities"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_cd92627a-948a-49e0-99c2-f9dda3006629" xlink:to="loc_us-gaap_OtherLiabilities_e3efa13a-1c8c-41d0-b3fa-d94fd9b203ba" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/CONSOLIDATEDSTATEMENTSOFINCOME" xlink:type="simple" xlink:href="cass-20241231.xsd#CONSOLIDATEDSTATEMENTSOFINCOME"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/CONSOLIDATEDSTATEMENTSOFINCOME" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LaborAndRelatedExpense_8a16ac22-1f54-4b59-9c64-a034aedba8e8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LaborAndRelatedExpense"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_03d14308-12d9-4456-a00b-1f568ca4f365" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensation"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LaborAndRelatedExpense_8a16ac22-1f54-4b59-9c64-a034aedba8e8" xlink:to="loc_us-gaap_ShareBasedCompensation_03d14308-12d9-4456-a00b-1f568ca4f365" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_OtherBenefits_99ca69dd-1b93-4fad-b527-8b280c30f37a" xlink:href="cass-20241231.xsd#cass_OtherBenefits"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LaborAndRelatedExpense_8a16ac22-1f54-4b59-9c64-a034aedba8e8" xlink:to="loc_cass_OtherBenefits_99ca69dd-1b93-4fad-b527-8b280c30f37a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_6917acdb-9a48-46c5-9b86-8b7faaf6cb31" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LaborAndRelatedExpense_8a16ac22-1f54-4b59-9c64-a034aedba8e8" xlink:to="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_6917acdb-9a48-46c5-9b86-8b7faaf6cb31" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_SalariesAndCommissions_72aadf46-6f9c-42d5-ba47-3bd2a28074ae" xlink:href="cass-20241231.xsd#cass_SalariesAndCommissions"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LaborAndRelatedExpense_8a16ac22-1f54-4b59-9c64-a034aedba8e8" xlink:to="loc_cass_SalariesAndCommissions_72aadf46-6f9c-42d5-ba47-3bd2a28074ae" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_320b77cd-589c-44ac-9a9d-0c7329e427a9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_e6245421-fd26-4b64-a635-57813e600590" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_320b77cd-589c-44ac-9a9d-0c7329e427a9" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_e6245421-fd26-4b64-a635-57813e600590" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_14015e1a-d118-40a2-9bc3-0a5ebdd40e94" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_320b77cd-589c-44ac-9a9d-0c7329e427a9" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_14015e1a-d118-40a2-9bc3-0a5ebdd40e94" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_b87d892c-539d-4e50-adb1-ad4839236ca0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Revenues_c926f546-6d4f-4945-891c-8ba7479eb759" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Revenues"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_b87d892c-539d-4e50-adb1-ad4839236ca0" xlink:to="loc_us-gaap_Revenues_c926f546-6d4f-4945-891c-8ba7479eb759" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestExpense_5d5c9502-11f9-46cf-ac0b-14cce6a01521" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestExpense"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_b87d892c-539d-4e50-adb1-ad4839236ca0" xlink:to="loc_us-gaap_NoninterestExpense_5d5c9502-11f9-46cf-ac0b-14cce6a01521" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestExpense_3c2d142b-5b33-4186-8fe3-7a14e322505e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestExpense"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquipmentExpense_a1dfaecf-8d98-4432-82fc-05eede2aa9bb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquipmentExpense"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NoninterestExpense_3c2d142b-5b33-4186-8fe3-7a14e322505e" xlink:to="loc_us-gaap_EquipmentExpense_a1dfaecf-8d98-4432-82fc-05eede2aa9bb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LaborAndRelatedExpense_0b92098f-7775-4fab-9082-8b15f6680ed1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LaborAndRelatedExpense"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NoninterestExpense_3c2d142b-5b33-4186-8fe3-7a14e322505e" xlink:to="loc_us-gaap_LaborAndRelatedExpense_0b92098f-7775-4fab-9082-8b15f6680ed1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_60116649-0fe5-43a6-8c7a-eddc84788084" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AmortizationOfIntangibleAssets"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NoninterestExpense_3c2d142b-5b33-4186-8fe3-7a14e322505e" xlink:to="loc_us-gaap_AmortizationOfIntangibleAssets_60116649-0fe5-43a6-8c7a-eddc84788084" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNoninterestExpense_bebadffa-133f-4a77-a897-24300ff822cc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherNoninterestExpense"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NoninterestExpense_3c2d142b-5b33-4186-8fe3-7a14e322505e" xlink:to="loc_us-gaap_OtherNoninterestExpense_bebadffa-133f-4a77-a897-24300ff822cc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OccupancyNet_ad12f3d7-0243-4f83-a71f-b6462645b267" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OccupancyNet"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NoninterestExpense_3c2d142b-5b33-4186-8fe3-7a14e322505e" xlink:to="loc_us-gaap_OccupancyNet_ad12f3d7-0243-4f83-a71f-b6462645b267" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_BadDebtExpense_b9813dfe-cef1-450d-b1e6-fefd8daab3d8" xlink:href="cass-20241231.xsd#cass_BadDebtExpense"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NoninterestExpense_3c2d142b-5b33-4186-8fe3-7a14e322505e" xlink:to="loc_cass_BadDebtExpense_b9813dfe-cef1-450d-b1e6-fefd8daab3d8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestIncome_ecddb197-88ac-4d61-ae3c-ef674ce6dec5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestIncome"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_a29d6cce-8b14-48e5-ab21-fdc4a5848c37" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NoninterestIncome_ecddb197-88ac-4d61-ae3c-ef674ce6dec5" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_a29d6cce-8b14-48e5-ab21-fdc4a5848c37" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_BankServiceFeesAndOtherRevenueNotFromContractWithCustomer_b741d4a6-bf6f-4e8f-9525-17a98651f603" xlink:href="cass-20241231.xsd#cass_BankServiceFeesAndOtherRevenueNotFromContractWithCustomer"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NoninterestIncome_ecddb197-88ac-4d61-ae3c-ef674ce6dec5" xlink:to="loc_cass_BankServiceFeesAndOtherRevenueNotFromContractWithCustomer_b741d4a6-bf6f-4e8f-9525-17a98651f603" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseOperating_947b1742-bc26-43e4-b2b6-fbefc4c30c83" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseOperating"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDeposits_74fe86e8-49b2-425a-89cf-3db3c16366dc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseDeposits"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestExpenseOperating_947b1742-bc26-43e4-b2b6-fbefc4c30c83" xlink:to="loc_us-gaap_InterestExpenseDeposits_74fe86e8-49b2-425a-89cf-3db3c16366dc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseShortTermBorrowings_3f2908d0-3401-49ae-b977-885e5ec3be0f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseShortTermBorrowings"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestExpenseOperating_947b1742-bc26-43e4-b2b6-fbefc4c30c83" xlink:to="loc_us-gaap_InterestExpenseShortTermBorrowings_3f2908d0-3401-49ae-b977-885e5ec3be0f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndDividendIncomeOperating_71aa1479-1301-4dac-95ab-0e129ec6dd4c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestAndDividendIncomeOperating"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndFeeIncomeLoansAndLeases_0644f6ff-f950-428e-9467-47ac81d1ca6a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestAndFeeIncomeLoansAndLeases"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestAndDividendIncomeOperating_71aa1479-1301-4dac-95ab-0e129ec6dd4c" xlink:to="loc_us-gaap_InterestAndFeeIncomeLoansAndLeases_0644f6ff-f950-428e-9467-47ac81d1ca6a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeSecuritiesTaxable_2260b621-ecba-40aa-a508-38c15e97effe" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeSecuritiesTaxable"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestAndDividendIncomeOperating_71aa1479-1301-4dac-95ab-0e129ec6dd4c" xlink:to="loc_us-gaap_InterestIncomeSecuritiesTaxable_2260b621-ecba-40aa-a508-38c15e97effe" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeSecuritiesTaxExempt_648ac61a-060e-44fc-90ea-891b63628dc6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeSecuritiesTaxExempt"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestAndDividendIncomeOperating_71aa1479-1301-4dac-95ab-0e129ec6dd4c" xlink:to="loc_us-gaap_InterestIncomeSecuritiesTaxExempt_648ac61a-060e-44fc-90ea-891b63628dc6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_InterestOnFederalFundsSoldAndOtherShortTermInvestments_1edfcba1-ebae-4aa5-8ef5-7a530e8aa6e5" xlink:href="cass-20241231.xsd#cass_InterestOnFederalFundsSoldAndOtherShortTermInvestments"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestAndDividendIncomeOperating_71aa1479-1301-4dac-95ab-0e129ec6dd4c" xlink:to="loc_cass_InterestOnFederalFundsSoldAndOtherShortTermInvestments_1edfcba1-ebae-4aa5-8ef5-7a530e8aa6e5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss_781a6d1d-e830-4e22-a675-d4e2846ed3e6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseNet_2b6ae7fb-70b5-4fb1-a93c-538056971a7d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeExpenseNet"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss_781a6d1d-e830-4e22-a675-d4e2846ed3e6" xlink:to="loc_us-gaap_InterestIncomeExpenseNet_2b6ae7fb-70b5-4fb1-a93c-538056971a7d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForLoanLossesExpensed_4114d8a9-6240-4682-bc43-447be9db26a9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProvisionForLoanLossesExpensed"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss_781a6d1d-e830-4e22-a675-d4e2846ed3e6" xlink:to="loc_us-gaap_ProvisionForLoanLossesExpensed_4114d8a9-6240-4682-bc43-447be9db26a9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseNet_25a9de60-86db-4c1c-a5d4-d8a1f5835d9a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeExpenseNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseOperating_e0a5db7f-11f0-4203-9135-2f302a1cba24" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseOperating"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestIncomeExpenseNet_25a9de60-86db-4c1c-a5d4-d8a1f5835d9a" xlink:to="loc_us-gaap_InterestExpenseOperating_e0a5db7f-11f0-4203-9135-2f302a1cba24" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndDividendIncomeOperating_20958312-253c-420a-8423-2694ad2341e2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestAndDividendIncomeOperating"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestIncomeExpenseNet_25a9de60-86db-4c1c-a5d4-d8a1f5835d9a" xlink:to="loc_us-gaap_InterestAndDividendIncomeOperating_20958312-253c-420a-8423-2694ad2341e2" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/CONSOLIDATEDSTATEMENTSOFCOMPREHENSIVEINCOME" xlink:type="simple" xlink:href="cass-20241231.xsd#CONSOLIDATEDSTATEMENTSOFCOMPREHENSIVEINCOME"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/CONSOLIDATEDSTATEMENTSOFCOMPREHENSIVEINCOME" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax_e3486081-e0df-47c6-ad31-610c80424cce" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ComprehensiveIncomeNetOfTax"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_169d066c-5cfa-4fe1-aacf-44faeda76b4a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_e3486081-e0df-47c6-ad31-610c80424cce" xlink:to="loc_us-gaap_NetIncomeLoss_169d066c-5cfa-4fe1-aacf-44faeda76b4a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_99c6ed78-d03c-4d5a-b01d-975ede759f97" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_e3486081-e0df-47c6-ad31-610c80424cce" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_99c6ed78-d03c-4d5a-b01d-975ede759f97" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_512d1f39-4bb6-47f8-a435-69871b4c365f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax_0c5d6bf4-c41c-401d-95cd-1904b2063e7b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_512d1f39-4bb6-47f8-a435-69871b4c365f" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax_0c5d6bf4-c41c-401d-95cd-1904b2063e7b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax_5bc536af-6a24-4ab0-9e8a-6a0f873c5e62" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_512d1f39-4bb6-47f8-a435-69871b4c365f" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax_5bc536af-6a24-4ab0-9e8a-6a0f873c5e62" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_e79c4902-e981-48d7-85e2-74937c5be37b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_512d1f39-4bb6-47f8-a435-69871b4c365f" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_e79c4902-e981-48d7-85e2-74937c5be37b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax_37f092ef-6a83-490b-b75c-01ca4827800b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_512d1f39-4bb6-47f8-a435-69871b4c365f" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax_37f092ef-6a83-490b-b75c-01ca4827800b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax_a66c9188-045e-4ea8-b992-3a4092194506" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_512d1f39-4bb6-47f8-a435-69871b4c365f" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax_a66c9188-045e-4ea8-b992-3a4092194506" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax_d7384e33-493e-4a7d-ad7d-6f5460ec3b04" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_512d1f39-4bb6-47f8-a435-69871b4c365f" xlink:to="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax_d7384e33-493e-4a7d-ad7d-6f5460ec3b04" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax_85045c8b-3a79-451d-808f-46e1e22127b4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_512d1f39-4bb6-47f8-a435-69871b4c365f" xlink:to="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax_85045c8b-3a79-451d-808f-46e1e22127b4" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWS" xlink:type="simple" xlink:href="cass-20241231.xsd#CONSOLIDATEDSTATEMENTSOFCASHFLOWS"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWS" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a1048d32-786e-47a0-a9b2-c82df7920b18" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_NetIncreaseDecreaseInAccountsAndDraftsReceivableFromCustomers_e853272e-f764-4895-a519-25c7babae70f" xlink:href="cass-20241231.xsd#cass_NetIncreaseDecreaseInAccountsAndDraftsReceivableFromCustomers"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a1048d32-786e-47a0-a9b2-c82df7920b18" xlink:to="loc_cass_NetIncreaseDecreaseInAccountsAndDraftsReceivableFromCustomers_e853272e-f764-4895-a519-25c7babae70f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_51e9e553-b826-4011-a596-ad82981ed609" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a1048d32-786e-47a0-a9b2-c82df7920b18" xlink:to="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_51e9e553-b826-4011-a596-ad82981ed609" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfDividendsCommonStock_ef34473b-c8fc-4c15-bc31-bcedd799795d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsOfDividendsCommonStock"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a1048d32-786e-47a0-a9b2-c82df7920b18" xlink:to="loc_us-gaap_PaymentsOfDividendsCommonStock_ef34473b-c8fc-4c15-bc31-bcedd799795d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_229ad5bb-8e79-40ae-9db1-db999d225fda" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromPaymentsForOtherFinancingActivities"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a1048d32-786e-47a0-a9b2-c82df7920b18" xlink:to="loc_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_229ad5bb-8e79-40ae-9db1-db999d225fda" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_NetIncreaseDecreaseInInterestBearingDemandAndSavingsDeposits_0c0d042c-4768-4196-b9a1-3ec536adba6e" xlink:href="cass-20241231.xsd#cass_NetIncreaseDecreaseInInterestBearingDemandAndSavingsDeposits"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a1048d32-786e-47a0-a9b2-c82df7920b18" xlink:to="loc_cass_NetIncreaseDecreaseInInterestBearingDemandAndSavingsDeposits_0c0d042c-4768-4196-b9a1-3ec536adba6e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_IncreaseDecreaseInAccountsAndDraftsPayable_9f0b817d-de68-4e2b-aaf4-0e292e0bd5df" xlink:href="cass-20241231.xsd#cass_IncreaseDecreaseInAccountsAndDraftsPayable"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a1048d32-786e-47a0-a9b2-c82df7920b18" xlink:to="loc_cass_IncreaseDecreaseInAccountsAndDraftsPayable_9f0b817d-de68-4e2b-aaf4-0e292e0bd5df" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInTimeDeposits_d359ddb3-9d36-476e-8a7e-6ff9abf82c18" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInTimeDeposits"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a1048d32-786e-47a0-a9b2-c82df7920b18" xlink:to="loc_us-gaap_IncreaseDecreaseInTimeDeposits_d359ddb3-9d36-476e-8a7e-6ff9abf82c18" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_NetIncreaseDecreaseInNoninterestBearingDemandDeposits_be9a4463-7c0f-456f-82c7-89cbfe675a9a" xlink:href="cass-20241231.xsd#cass_NetIncreaseDecreaseInNoninterestBearingDemandDeposits"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_a1048d32-786e-47a0-a9b2-c82df7920b18" xlink:to="loc_cass_NetIncreaseDecreaseInNoninterestBearingDemandDeposits_be9a4463-7c0f-456f-82c7-89cbfe675a9a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_0c4a5c6b-85cc-4a4b-b3ca-67309e2c252d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_3899fa02-46aa-4a2a-9405-928632e472ba" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_0c4a5c6b-85cc-4a4b-b3ca-67309e2c252d" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_3899fa02-46aa-4a2a-9405-928632e472ba" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_cb8e2819-c936-43d5-bb8c-ebbcd2f55174" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_0c4a5c6b-85cc-4a4b-b3ca-67309e2c252d" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_cb8e2819-c936-43d5-bb8c-ebbcd2f55174" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_eb4d33ae-783e-4a86-8b3a-b79976303a96" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_0c4a5c6b-85cc-4a4b-b3ca-67309e2c252d" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_eb4d33ae-783e-4a86-8b3a-b79976303a96" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_09eb1dd8-908b-40aa-8804-3bfc8b9ba061" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_eb50deea-dc03-4d40-9185-5b590388bd58" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_09eb1dd8-908b-40aa-8804-3bfc8b9ba061" xlink:to="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_eb50deea-dc03-4d40-9185-5b590388bd58" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt_14c8d98d-88d9-4f38-9b68-ab821059ce03" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_09eb1dd8-908b-40aa-8804-3bfc8b9ba061" xlink:to="loc_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt_14c8d98d-88d9-4f38-9b68-ab821059ce03" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_IncreaseDecreaseInPaymentsInExcessOfFunding_b153b1a0-d329-4a2e-a6e4-7525be306551" xlink:href="cass-20241231.xsd#cass_IncreaseDecreaseInPaymentsInExcessOfFunding"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_09eb1dd8-908b-40aa-8804-3bfc8b9ba061" xlink:to="loc_cass_IncreaseDecreaseInPaymentsInExcessOfFunding_b153b1a0-d329-4a2e-a6e4-7525be306551" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_66fec0f0-3510-4b91-90bb-153c7a1bf9bf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_09eb1dd8-908b-40aa-8804-3bfc8b9ba061" xlink:to="loc_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_66fec0f0-3510-4b91-90bb-153c7a1bf9bf" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForProceedsFromLoansAndLeases_78f3856a-65a1-4d43-9954-cb0057d6d311" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsForProceedsFromLoansAndLeases"/>
    <link:calculationArc order="5" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_09eb1dd8-908b-40aa-8804-3bfc8b9ba061" xlink:to="loc_us-gaap_PaymentsForProceedsFromLoansAndLeases_78f3856a-65a1-4d43-9954-cb0057d6d311" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_PaymentsForAssetAcquisitions_95dc2b64-6e45-4f92-8105-ba40238e61f6" xlink:href="cass-20241231.xsd#cass_PaymentsForAssetAcquisitions"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_09eb1dd8-908b-40aa-8804-3bfc8b9ba061" xlink:to="loc_cass_PaymentsForAssetAcquisitions_95dc2b64-6e45-4f92-8105-ba40238e61f6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities_ed318f75-5483-49c0-a80b-b0e353ab944a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_09eb1dd8-908b-40aa-8804-3bfc8b9ba061" xlink:to="loc_us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities_ed318f75-5483-49c0-a80b-b0e353ab944a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireLifeInsurancePolicies_9b4d155a-6b65-4fef-95b8-3950f596f794" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsToAcquireLifeInsurancePolicies"/>
    <link:calculationArc order="8" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_09eb1dd8-908b-40aa-8804-3bfc8b9ba061" xlink:to="loc_us-gaap_PaymentsToAcquireLifeInsurancePolicies_9b4d155a-6b65-4fef-95b8-3950f596f794" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2f6b930e-3f89-4d9e-9e5e-2a70195618e6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtAndEquitySecuritiesGainLoss_30467a6f-eeec-4032-a8fa-5e3cd94d8af3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtAndEquitySecuritiesGainLoss"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2f6b930e-3f89-4d9e-9e5e-2a70195618e6" xlink:to="loc_us-gaap_DebtAndEquitySecuritiesGainLoss_30467a6f-eeec-4032-a8fa-5e3cd94d8af3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Depreciation_545a2337-68a7-4bf9-a280-54c17ce387aa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Depreciation"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2f6b930e-3f89-4d9e-9e5e-2a70195618e6" xlink:to="loc_us-gaap_Depreciation_545a2337-68a7-4bf9-a280-54c17ce387aa" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_3b855dbc-baab-4f4f-afc0-9837353c309f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2f6b930e-3f89-4d9e-9e5e-2a70195618e6" xlink:to="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_3b855dbc-baab-4f4f-afc0-9837353c309f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInPensionPlanObligations_ea623152-a3d8-47b4-abd6-1f0936154c8e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInPensionPlanObligations"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2f6b930e-3f89-4d9e-9e5e-2a70195618e6" xlink:to="loc_us-gaap_IncreaseDecreaseInPensionPlanObligations_ea623152-a3d8-47b4-abd6-1f0936154c8e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_0522fae4-971c-45f9-a064-03bce5d291e8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLoss"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2f6b930e-3f89-4d9e-9e5e-2a70195618e6" xlink:to="loc_us-gaap_NetIncomeLoss_0522fae4-971c-45f9-a064-03bce5d291e8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable_31472b1b-e324-44ba-aebd-9f47873aac21" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2f6b930e-3f89-4d9e-9e5e-2a70195618e6" xlink:to="loc_us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable_31472b1b-e324-44ba-aebd-9f47873aac21" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherOperatingActivitiesCashFlowStatement_635d100a-d2db-4071-914f-fa2467d3c0ed" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherOperatingActivitiesCashFlowStatement"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2f6b930e-3f89-4d9e-9e5e-2a70195618e6" xlink:to="loc_us-gaap_OtherOperatingActivitiesCashFlowStatement_635d100a-d2db-4071-914f-fa2467d3c0ed" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_164e4022-0d81-4ce9-b002-6e0401b84e74" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AmortizationOfIntangibleAssets"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2f6b930e-3f89-4d9e-9e5e-2a70195618e6" xlink:to="loc_us-gaap_AmortizationOfIntangibleAssets_164e4022-0d81-4ce9-b002-6e0401b84e74" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForLoanLossesExpensed_9e1f0c6b-d0c7-45c2-86d0-71049a5cc01d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProvisionForLoanLossesExpensed"/>
    <link:calculationArc order="9" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2f6b930e-3f89-4d9e-9e5e-2a70195618e6" xlink:to="loc_us-gaap_ProvisionForLoanLossesExpensed_9e1f0c6b-d0c7-45c2-86d0-71049a5cc01d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_fc1438db-38f4-4229-baaf-ba9af95e6fa4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensation"/>
    <link:calculationArc order="10" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2f6b930e-3f89-4d9e-9e5e-2a70195618e6" xlink:to="loc_us-gaap_ShareBasedCompensation_fc1438db-38f4-4229-baaf-ba9af95e6fa4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_cb357629-9313-43cb-9741-e5f14fedbd68" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments"/>
    <link:calculationArc order="11" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2f6b930e-3f89-4d9e-9e5e-2a70195618e6" xlink:to="loc_us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_cb357629-9313-43cb-9741-e5f14fedbd68" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_9d41cd22-99a5-4554-921e-25bb42af2742" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable"/>
    <link:calculationArc order="12" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2f6b930e-3f89-4d9e-9e5e-2a70195618e6" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_9d41cd22-99a5-4554-921e-25bb42af2742" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_5037f5f6-3a72-49a9-95a7-3330f1da1ebf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeLossFromEquityMethodInvestments"/>
    <link:calculationArc order="13" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2f6b930e-3f89-4d9e-9e5e-2a70195618e6" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_5037f5f6-3a72-49a9-95a7-3330f1da1ebf" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/InvestmentSecuritiesScheduleofInvestmentSecuritiesDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#InvestmentSecuritiesScheduleofInvestmentSecuritiesDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/InvestmentSecuritiesScheduleofInvestmentSecuritiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_c7022deb-1c75-4897-801c-846b25fd85c9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_47934d85-f5bf-465e-be73-42b1bc8945f2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_c7022deb-1c75-4897-801c-846b25fd85c9" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_47934d85-f5bf-465e-be73-42b1bc8945f2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_3bc995e8-fb7d-4500-b0f5-6256c6c9e6b1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_c7022deb-1c75-4897-801c-846b25fd85c9" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_3bc995e8-fb7d-4500-b0f5-6256c6c9e6b1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_84be3d35-da35-4647-ada9-6372d544db76" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_c7022deb-1c75-4897-801c-846b25fd85c9" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_84be3d35-da35-4647-ada9-6372d544db76" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/InvestmentSecuritiesScheduleoftheFairValuesofSecuritieswithUnrealizedLossesDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#InvestmentSecuritiesScheduleoftheFairValuesofSecuritieswithUnrealizedLossesDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/InvestmentSecuritiesScheduleoftheFairValuesofSecuritieswithUnrealizedLossesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_89a858ba-ae76-4af9-9592-643b819aee09" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_ba4221a1-c1cb-4d0a-84d1-dcb597069bb6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_89a858ba-ae76-4af9-9592-643b819aee09" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_ba4221a1-c1cb-4d0a-84d1-dcb597069bb6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_0667f1bf-e0d9-49cb-8797-e43ca30295ed" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_89a858ba-ae76-4af9-9592-643b819aee09" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_0667f1bf-e0d9-49cb-8797-e43ca30295ed" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition_ea089870-92ec-4e5e-8ae5-390dfe145932" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months_b2f4f21d-5454-4c28-9c37-5db00afbcc70" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition_ea089870-92ec-4e5e-8ae5-390dfe145932" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months_b2f4f21d-5454-4c28-9c37-5db00afbcc70" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger_bdecde46-1550-4894-a3e2-1d3ae371d2fa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition_ea089870-92ec-4e5e-8ae5-390dfe145932" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger_bdecde46-1550-4894-a3e2-1d3ae371d2fa" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/InvestmentSecuritiesScheduleofAmortizedCostandFairValueofInvestmentSecuritiesDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#InvestmentSecuritiesScheduleofAmortizedCostandFairValueofInvestmentSecuritiesDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/InvestmentSecuritiesScheduleofAmortizedCostandFairValueofInvestmentSecuritiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_119a0159-91d8-480b-b325-a75364160bf8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_4eee2044-e9a2-431e-8488-b7015919e1dc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_119a0159-91d8-480b-b325-a75364160bf8" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_4eee2044-e9a2-431e-8488-b7015919e1dc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_1fba51f0-7253-4f8a-b76f-4d35fc149642" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_119a0159-91d8-480b-b325-a75364160bf8" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_1fba51f0-7253-4f8a-b76f-4d35fc149642" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_6b817f61-313d-44c1-ae12-a09b42fbd1d9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_119a0159-91d8-480b-b325-a75364160bf8" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_6b817f61-313d-44c1-ae12-a09b42fbd1d9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue_1e23d1d7-72a4-467d-9501-dbdc36efcc1f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_119a0159-91d8-480b-b325-a75364160bf8" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue_1e23d1d7-72a4-467d-9501-dbdc36efcc1f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_e70f910b-02f3-41a6-860b-683ecdad522f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost_17933589-d7c0-4a03-b76b-82eac2030a3b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_e70f910b-02f3-41a6-860b-683ecdad522f" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost_17933589-d7c0-4a03-b76b-82eac2030a3b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost_6f8f9549-3719-4abf-bd4e-750e54619716" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_e70f910b-02f3-41a6-860b-683ecdad522f" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost_6f8f9549-3719-4abf-bd4e-750e54619716" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_2a8036b3-a2d6-4426-b120-8827e27326b7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_e70f910b-02f3-41a6-860b-683ecdad522f" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_2a8036b3-a2d6-4426-b120-8827e27326b7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost_4e46c707-cdb6-490e-bf20-5c0bebc001d6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_e70f910b-02f3-41a6-860b-683ecdad522f" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost_4e46c707-cdb6-490e-bf20-5c0bebc001d6" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/PremisesandEquipmentSummaryofPremisesandEquipmentDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#PremisesandEquipmentSummaryofPremisesandEquipmentDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/PremisesandEquipmentSummaryofPremisesandEquipmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_0556c626-9457-4858-8f35-3a12ab992cbf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross_d93ff146-c484-44b6-a702-baa2b9e14c12" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PropertyPlantAndEquipmentGross"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet_0556c626-9457-4858-8f35-3a12ab992cbf" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentGross_d93ff146-c484-44b6-a702-baa2b9e14c12" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_02a8492f-f3c9-401d-86e1-a98489f57f51" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet_0556c626-9457-4858-8f35-3a12ab992cbf" xlink:to="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_02a8492f-f3c9-401d-86e1-a98489f57f51" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/AcquiredIntangibleAssetsScheduleofIntangibleAssetsandGoodwillDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#AcquiredIntangibleAssetsScheduleofIntangibleAssetsandGoodwillDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/AcquiredIntangibleAssetsScheduleofIntangibleAssetsandGoodwillDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetIncludingGoodwill_b2c1a218-2cc6-452c-8c0b-3e0f7aa061a6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IntangibleAssetsNetIncludingGoodwill"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillGross_37d1ca2f-00db-4c67-abe4-a1c7a6c3e9ac" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GoodwillGross"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsNetIncludingGoodwill_b2c1a218-2cc6-452c-8c0b-3e0f7aa061a6" xlink:to="loc_us-gaap_GoodwillGross_37d1ca2f-00db-4c67-abe4-a1c7a6c3e9ac" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_4ba27b69-1224-423d-b3f1-012747fa6f7b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsNetIncludingGoodwill_b2c1a218-2cc6-452c-8c0b-3e0f7aa061a6" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_4ba27b69-1224-423d-b3f1-012747fa6f7b" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/InterestBearingDepositsScheduleofInterestbearingDepositsDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#InterestBearingDepositsScheduleofInterestbearingDepositsDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/InterestBearingDepositsScheduleofInterestbearingDepositsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestBearingDepositLiabilities_9a82b556-dc24-46fa-8ad2-250c365bf64e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestBearingDepositLiabilities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DemandDepositAccounts_3259fd89-bc38-4817-b54d-f60842bfd7d6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DemandDepositAccounts"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestBearingDepositLiabilities_9a82b556-dc24-46fa-8ad2-250c365bf64e" xlink:to="loc_us-gaap_DemandDepositAccounts_3259fd89-bc38-4817-b54d-f60842bfd7d6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsSavingsDeposits_158d392a-00b9-46ae-bd9a-ab1530c9bcf2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DepositsSavingsDeposits"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestBearingDepositLiabilities_9a82b556-dc24-46fa-8ad2-250c365bf64e" xlink:to="loc_us-gaap_DepositsSavingsDeposits_158d392a-00b9-46ae-bd9a-ab1530c9bcf2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositsLessThan100000_675d0568-df53-47cf-9fd7-5c61fa16c8f3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TimeDepositsLessThan100000"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestBearingDepositLiabilities_9a82b556-dc24-46fa-8ad2-250c365bf64e" xlink:to="loc_us-gaap_TimeDepositsLessThan100000_675d0568-df53-47cf-9fd7-5c61fa16c8f3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_TimeDepositsMoreThan100000LessThan250000_7b243c79-579c-4152-abb5-c3d15527b9e8" xlink:href="cass-20241231.xsd#cass_TimeDepositsMoreThan100000LessThan250000"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestBearingDepositLiabilities_9a82b556-dc24-46fa-8ad2-250c365bf64e" xlink:to="loc_cass_TimeDepositsMoreThan100000LessThan250000_7b243c79-579c-4152-abb5-c3d15527b9e8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_TimeDepositsMoreThan250000_1063307a-2f2b-4672-a50a-7bfc43d3397c" xlink:href="cass-20241231.xsd#cass_TimeDepositsMoreThan250000"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestBearingDepositLiabilities_9a82b556-dc24-46fa-8ad2-250c365bf64e" xlink:to="loc_cass_TimeDepositsMoreThan250000_1063307a-2f2b-4672-a50a-7bfc43d3397c" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/InterestBearingDepositsScheduleofInterestonDepositsDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#InterestBearingDepositsScheduleofInterestonDepositsDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/InterestBearingDepositsScheduleofInterestonDepositsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDeposits_9f0dbd31-be2d-4c6d-8ccd-fae517dbf27f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseDeposits"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDemandDepositAccounts_798ca9bc-805d-4282-bef0-7f10b0254265" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseDemandDepositAccounts"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestExpenseDeposits_9f0dbd31-be2d-4c6d-8ccd-fae517dbf27f" xlink:to="loc_us-gaap_InterestExpenseDemandDepositAccounts_798ca9bc-805d-4282-bef0-7f10b0254265" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseSavingsDeposits_2fed76f4-8458-422e-9a2d-bf6f1b3c650f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseSavingsDeposits"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestExpenseDeposits_9f0dbd31-be2d-4c6d-8ccd-fae517dbf27f" xlink:to="loc_us-gaap_InterestExpenseSavingsDeposits_2fed76f4-8458-422e-9a2d-bf6f1b3c650f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseTimeDepositsLessThan100000_fc751e92-f52f-4241-b32d-f79e34da73cf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseTimeDepositsLessThan100000"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestExpenseDeposits_9f0dbd31-be2d-4c6d-8ccd-fae517dbf27f" xlink:to="loc_us-gaap_InterestExpenseTimeDepositsLessThan100000_fc751e92-f52f-4241-b32d-f79e34da73cf" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_InterestExpenseTimeDeposits100000OrMoreAndLessThan250000_044b5531-5177-42cc-901f-af977fc20e02" xlink:href="cass-20241231.xsd#cass_InterestExpenseTimeDeposits100000OrMoreAndLessThan250000"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestExpenseDeposits_9f0dbd31-be2d-4c6d-8ccd-fae517dbf27f" xlink:to="loc_cass_InterestExpenseTimeDeposits100000OrMoreAndLessThan250000_044b5531-5177-42cc-901f-af977fc20e02" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_InterestExpenseTimeDeposits250000OrMore_be6eea33-70f1-43cb-bab6-b0b90846e2da" xlink:href="cass-20241231.xsd#cass_InterestExpenseTimeDeposits250000OrMore"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestExpenseDeposits_9f0dbd31-be2d-4c6d-8ccd-fae517dbf27f" xlink:to="loc_cass_InterestExpenseTimeDeposits250000OrMore_be6eea33-70f1-43cb-bab6-b0b90846e2da" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/InterestBearingDepositsScheduleofMaturitiesofTimeDepositsDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#InterestBearingDepositsScheduleofMaturitiesofTimeDepositsDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/InterestBearingDepositsScheduleofMaturitiesofTimeDepositsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDeposits_f5f43e59-4221-4e32-8462-8399269883b3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TimeDeposits"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositMaturitiesYearOne_04f2e1ed-8539-4b46-a8fd-e378b202ae2e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TimeDepositMaturitiesYearOne"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_TimeDeposits_f5f43e59-4221-4e32-8462-8399269883b3" xlink:to="loc_us-gaap_TimeDepositMaturitiesYearOne_04f2e1ed-8539-4b46-a8fd-e378b202ae2e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositMaturitiesYearTwo_00bb53f3-2ac0-4c8c-a1c7-f35a4864d718" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TimeDepositMaturitiesYearTwo"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_TimeDeposits_f5f43e59-4221-4e32-8462-8399269883b3" xlink:to="loc_us-gaap_TimeDepositMaturitiesYearTwo_00bb53f3-2ac0-4c8c-a1c7-f35a4864d718" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositMaturitiesYearThree_d2c6d808-bd24-4ed6-aa82-4e801509b98d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TimeDepositMaturitiesYearThree"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_TimeDeposits_f5f43e59-4221-4e32-8462-8399269883b3" xlink:to="loc_us-gaap_TimeDepositMaturitiesYearThree_d2c6d808-bd24-4ed6-aa82-4e801509b98d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositMaturitiesYearFour_a1be58d3-b5b2-4ca2-957e-56db3ebc79d6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TimeDepositMaturitiesYearFour"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_TimeDeposits_f5f43e59-4221-4e32-8462-8399269883b3" xlink:to="loc_us-gaap_TimeDepositMaturitiesYearFour_a1be58d3-b5b2-4ca2-957e-56db3ebc79d6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositMaturitiesYearFive_8e31d0f0-668b-4d8b-a484-61a65e68d46e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TimeDepositMaturitiesYearFive"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_TimeDeposits_f5f43e59-4221-4e32-8462-8399269883b3" xlink:to="loc_us-gaap_TimeDepositMaturitiesYearFive_8e31d0f0-668b-4d8b-a484-61a65e68d46e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_TimeDepositsWeightedAverageInterestRateAggregate_98b28965-1518-48d5-ac38-00ff8259bc69" xlink:href="cass-20241231.xsd#cass_TimeDepositsWeightedAverageInterestRateAggregate"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositsWeightedAverageInterestRateMaturitiesYearOne_830930ba-11a5-4469-99d5-c53a515d2376" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TimeDepositsWeightedAverageInterestRateMaturitiesYearOne"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_cass_TimeDepositsWeightedAverageInterestRateAggregate_98b28965-1518-48d5-ac38-00ff8259bc69" xlink:to="loc_us-gaap_TimeDepositsWeightedAverageInterestRateMaturitiesYearOne_830930ba-11a5-4469-99d5-c53a515d2376" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositsWeightedAverageInterestRateMaturitiesYearTwo_3b273f86-a5ad-450b-8c6d-3b6d7981bd8f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TimeDepositsWeightedAverageInterestRateMaturitiesYearTwo"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_cass_TimeDepositsWeightedAverageInterestRateAggregate_98b28965-1518-48d5-ac38-00ff8259bc69" xlink:to="loc_us-gaap_TimeDepositsWeightedAverageInterestRateMaturitiesYearTwo_3b273f86-a5ad-450b-8c6d-3b6d7981bd8f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositsWeightedAverageInterestRateMaturitiesYearThree_1834a5df-a260-44d4-9e8f-393b47b54b86" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TimeDepositsWeightedAverageInterestRateMaturitiesYearThree"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_cass_TimeDepositsWeightedAverageInterestRateAggregate_98b28965-1518-48d5-ac38-00ff8259bc69" xlink:to="loc_us-gaap_TimeDepositsWeightedAverageInterestRateMaturitiesYearThree_1834a5df-a260-44d4-9e8f-393b47b54b86" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositsWeightedAverageInterestRateMaturitiesYearFour_2400583d-02ca-4d1c-b6df-8653b6407181" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TimeDepositsWeightedAverageInterestRateMaturitiesYearFour"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_cass_TimeDepositsWeightedAverageInterestRateAggregate_98b28965-1518-48d5-ac38-00ff8259bc69" xlink:to="loc_us-gaap_TimeDepositsWeightedAverageInterestRateMaturitiesYearFour_2400583d-02ca-4d1c-b6df-8653b6407181" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositsWeightedAverageInterestRateMaturitiesYearFive_83e48eb6-49f5-4082-beb9-308805dcfe9d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TimeDepositsWeightedAverageInterestRateMaturitiesYearFive"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_cass_TimeDepositsWeightedAverageInterestRateAggregate_98b28965-1518-48d5-ac38-00ff8259bc69" xlink:to="loc_us-gaap_TimeDepositsWeightedAverageInterestRateMaturitiesYearFive_83e48eb6-49f5-4082-beb9-308805dcfe9d" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/CommonStockandEarningsperShareScheduleofCalculationsofBasicandDilutedEarningsPerShareDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#CommonStockandEarningsperShareScheduleofCalculationsofBasicandDilutedEarningsPerShareDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/CommonStockandEarningsperShareScheduleofCalculationsofBasicandDilutedEarningsPerShareDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_c8ac2e28-4697-49a0-a95b-9200bac267ea" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_2d4e5324-6a10-4aab-a95a-7a6ce4a217c5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_c8ac2e28-4697-49a0-a95b-9200bac267ea" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_2d4e5324-6a10-4aab-a95a-7a6ce4a217c5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_4615e739-7ab5-480b-934a-5500755c97d2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_c8ac2e28-4697-49a0-a95b-9200bac267ea" xlink:to="loc_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_4615e739-7ab5-480b-934a-5500755c97d2" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/EmployeeBenefitPlansScheduleofProjectedBenefitObligationDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#EmployeeBenefitPlansScheduleofProjectedBenefitObligationDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/EmployeeBenefitPlansScheduleofProjectedBenefitObligationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanFundedStatusOfPlan_ac1de8a5-19cb-4d76-958e-42e610dba685" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanFundedStatusOfPlan"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_039504fb-f69a-4d6a-9041-16747ecbb97f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanFairValueOfPlanAssets"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanFundedStatusOfPlan_ac1de8a5-19cb-4d76-958e-42e610dba685" xlink:to="loc_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_039504fb-f69a-4d6a-9041-16747ecbb97f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanBenefitObligation_66bec546-e274-439b-b391-e80f2af8577d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanBenefitObligation"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanFundedStatusOfPlan_ac1de8a5-19cb-4d76-958e-42e610dba685" xlink:to="loc_us-gaap_DefinedBenefitPlanBenefitObligation_66bec546-e274-439b-b391-e80f2af8577d" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/EmployeeBenefitPlansScheduleofPlansPensionCostDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#EmployeeBenefitPlansScheduleofPlansPensionCostDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/EmployeeBenefitPlansScheduleofPlansPensionCostDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_0e49c1ab-8d1e-4a10-be5f-b35e9088aac8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit_c58c2697-6421-4033-b31d-f3a546a240ae" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_0e49c1ab-8d1e-4a10-be5f-b35e9088aac8" xlink:to="loc_us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit_c58c2697-6421-4033-b31d-f3a546a240ae" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanServiceCost_f7b63e1d-789c-4255-8a48-c8dd09c746c6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanServiceCost"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_0e49c1ab-8d1e-4a10-be5f-b35e9088aac8" xlink:to="loc_us-gaap_DefinedBenefitPlanServiceCost_f7b63e1d-789c-4255-8a48-c8dd09c746c6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanInterestCost_840a8f2a-b331-4a4f-964c-d4bf16b2db69" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanInterestCost"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_0e49c1ab-8d1e-4a10-be5f-b35e9088aac8" xlink:to="loc_us-gaap_DefinedBenefitPlanInterestCost_840a8f2a-b331-4a4f-964c-d4bf16b2db69" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_28b88c36-46da-4a1d-9a9d-e5222103c2e5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_0e49c1ab-8d1e-4a10-be5f-b35e9088aac8" xlink:to="loc_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_28b88c36-46da-4a1d-9a9d-e5222103c2e5" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/EmployeeBenefitPlansScheduleofthePretaxamountsinAccumulatedOtherComprehensiveLossDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#EmployeeBenefitPlansScheduleofthePretaxamountsinAccumulatedOtherComprehensiveLossDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/EmployeeBenefitPlansScheduleofthePretaxamountsinAccumulatedOtherComprehensiveLossDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax_3dbbca90-e2f7-440e-9c89-15dabb83c6d4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax_fe009a97-859c-4b4b-8876-0c5b96c53e4e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax_3dbbca90-e2f7-440e-9c89-15dabb83c6d4" xlink:to="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax_fe009a97-859c-4b4b-8876-0c5b96c53e4e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax_e3d7ff6c-a8b9-410f-b00f-2f49035d04ce" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax_3dbbca90-e2f7-440e-9c89-15dabb83c6d4" xlink:to="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax_e3d7ff6c-a8b9-410f-b00f-2f49035d04ce" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/OtherOperatingExpenseDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#OtherOperatingExpenseDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/OtherOperatingExpenseDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNoninterestExpense_7a07e530-afe2-4866-956f-037866807eed" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherNoninterestExpense"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketingAndAdvertisingExpense_924b5e01-9ec2-4706-91b6-19f0b2347d1d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketingAndAdvertisingExpense"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherNoninterestExpense_7a07e530-afe2-4866-956f-037866807eed" xlink:to="loc_us-gaap_MarketingAndAdvertisingExpense_924b5e01-9ec2-4706-91b6-19f0b2347d1d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_OutsideServiceFees_1767213a-31b3-49c4-b65f-2752b9946953" xlink:href="cass-20241231.xsd#cass_OutsideServiceFees"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherNoninterestExpense_7a07e530-afe2-4866-956f-037866807eed" xlink:to="loc_cass_OutsideServiceFees_1767213a-31b3-49c4-b65f-2752b9946953" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InformationTechnologyAndDataProcessing_34764e24-94bc-4ff7-851d-4bc2f053c7a1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InformationTechnologyAndDataProcessing"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherNoninterestExpense_7a07e530-afe2-4866-956f-037866807eed" xlink:to="loc_us-gaap_InformationTechnologyAndDataProcessing_34764e24-94bc-4ff7-851d-4bc2f053c7a1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherExpenses_dc0086e6-5da9-4250-ba5d-01549adb3052" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherExpenses"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherNoninterestExpense_7a07e530-afe2-4866-956f-037866807eed" xlink:to="loc_us-gaap_OtherExpenses_dc0086e6-5da9-4250-ba5d-01549adb3052" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/IncomeTaxesComponentsofIncomeTaxExpenseBenefitDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#IncomeTaxesComponentsofIncomeTaxExpenseBenefitDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/IncomeTaxesComponentsofIncomeTaxExpenseBenefitDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_8bb2c4ea-486c-4c47-9268-1ace77e1eeba" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CurrentFederalTaxExpenseBenefit_429fedf0-00ac-4e25-8a60-50b49cc5eae1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CurrentFederalTaxExpenseBenefit"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_8bb2c4ea-486c-4c47-9268-1ace77e1eeba" xlink:to="loc_us-gaap_CurrentFederalTaxExpenseBenefit_429fedf0-00ac-4e25-8a60-50b49cc5eae1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CurrentStateAndLocalTaxExpenseBenefit_f78d24e2-12a1-4001-b27b-99bfb5d206dd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CurrentStateAndLocalTaxExpenseBenefit"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_8bb2c4ea-486c-4c47-9268-1ace77e1eeba" xlink:to="loc_us-gaap_CurrentStateAndLocalTaxExpenseBenefit_f78d24e2-12a1-4001-b27b-99bfb5d206dd" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_4146a07b-b100-4db7-8725-afa02953aac1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredFederalIncomeTaxExpenseBenefit"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_8bb2c4ea-486c-4c47-9268-1ace77e1eeba" xlink:to="loc_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_4146a07b-b100-4db7-8725-afa02953aac1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_0370afd3-7f9e-460d-95ca-c3ce768a969e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_8bb2c4ea-486c-4c47-9268-1ace77e1eeba" xlink:to="loc_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_0370afd3-7f9e-460d-95ca-c3ce768a969e" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/IncomeTaxesScheduleofReconciliationofExpectedIncomeTaxExpenseBenefitDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#IncomeTaxesScheduleofReconciliationofExpectedIncomeTaxExpenseBenefitDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/IncomeTaxesScheduleofReconciliationofExpectedIncomeTaxExpenseBenefitDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_3e99b0ba-816d-4713-a56e-68763778efdf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationOtherAdjustments_c6455aac-6021-48f3-baf9-1a449096755b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeTaxReconciliationOtherAdjustments"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_3e99b0ba-816d-4713-a56e-68763778efdf" xlink:to="loc_us-gaap_IncomeTaxReconciliationOtherAdjustments_c6455aac-6021-48f3-baf9-1a449096755b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes_bfcd3c04-5e46-44f3-8bd5-0b2782a2cdb7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_3e99b0ba-816d-4713-a56e-68763778efdf" xlink:to="loc_us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes_bfcd3c04-5e46-44f3-8bd5-0b2782a2cdb7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost_82cd53e1-ac8c-40e0-94c8-e77e3a930783" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_3e99b0ba-816d-4713-a56e-68763778efdf" xlink:to="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost_82cd53e1-ac8c-40e0-94c8-e77e3a930783" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_d8eee92c-ff92-40d0-b1e4-53895af94888" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_3e99b0ba-816d-4713-a56e-68763778efdf" xlink:to="loc_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_d8eee92c-ff92-40d0-b1e4-53895af94888" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationTaxExemptIncome_2897c2c5-cdaf-4e7c-9ca2-46aab51ddb67" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeTaxReconciliationTaxExemptIncome"/>
    <link:calculationArc order="5" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_3e99b0ba-816d-4713-a56e-68763778efdf" xlink:to="loc_us-gaap_IncomeTaxReconciliationTaxExemptIncome_2897c2c5-cdaf-4e7c-9ca2-46aab51ddb67" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationTaxCredits_efda1eb1-efb6-492a-9b44-b08e46ca8bae" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeTaxReconciliationTaxCredits"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_3e99b0ba-816d-4713-a56e-68763778efdf" xlink:to="loc_us-gaap_IncomeTaxReconciliationTaxCredits_efda1eb1-efb6-492a-9b44-b08e46ca8bae" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsNet_1e21a0d3-221a-491f-a750-79bb0a47f73f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxAssetsNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions_2a778e83-b19a-4be1-adaa-54e53bf42d83" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsNet_1e21a0d3-221a-491f-a750-79bb0a47f73f" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions_2a778e83-b19a-4be1-adaa-54e53bf42d83" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost_194a8060-9316-426b-abc1-fc2a2d459a0e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsNet_1e21a0d3-221a-491f-a750-79bb0a47f73f" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost_194a8060-9316-426b-abc1-fc2a2d459a0e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses_ea543bb0-a5a6-4a29-92d5-9a685575cc55" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsNet_1e21a0d3-221a-491f-a750-79bb0a47f73f" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses_ea543bb0-a5a6-4a29-92d5-9a685575cc55" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross_2dd10b9b-c1e2-4211-af25-f070c59c1e1a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsNet_1e21a0d3-221a-491f-a750-79bb0a47f73f" xlink:to="loc_us-gaap_DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross_2dd10b9b-c1e2-4211-af25-f070c59c1e1a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsInProcessResearchAndDevelopment_3dfc2b23-0c0e-45d6-9e17-751a6fe5abf9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxAssetsInProcessResearchAndDevelopment"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsNet_1e21a0d3-221a-491f-a750-79bb0a47f73f" xlink:to="loc_us-gaap_DeferredTaxAssetsInProcessResearchAndDevelopment_3dfc2b23-0c0e-45d6-9e17-751a6fe5abf9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_DeferredTaxAssetLeaseLiability_d22bca49-a35b-44cb-bdb7-a3bff7aeddcb" xlink:href="cass-20241231.xsd#cass_DeferredTaxAssetLeaseLiability"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsNet_1e21a0d3-221a-491f-a750-79bb0a47f73f" xlink:to="loc_cass_DeferredTaxAssetLeaseLiability_d22bca49-a35b-44cb-bdb7-a3bff7aeddcb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsOther_e5b86fc5-ca60-4bc3-b85f-134c8da2ac61" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxAssetsOther"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsNet_1e21a0d3-221a-491f-a750-79bb0a47f73f" xlink:to="loc_us-gaap_DeferredTaxAssetsOther_e5b86fc5-ca60-4bc3-b85f-134c8da2ac61" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits_b112a994-1893-4c6c-b203-74094f20e08f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsNet_1e21a0d3-221a-491f-a750-79bb0a47f73f" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits_b112a994-1893-4c6c-b203-74094f20e08f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilities_88ef99dd-7c6d-42e6-b3d8-bd296c013f08" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxLiabilities"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_DeferredTaxLiabilitiesPensionCosts_77796cfa-8f2f-4b38-9f34-fd1b6ebd63af" xlink:href="cass-20241231.xsd#cass_DeferredTaxLiabilitiesPensionCosts"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxLiabilities_88ef99dd-7c6d-42e6-b3d8-bd296c013f08" xlink:to="loc_cass_DeferredTaxLiabilitiesPensionCosts_77796cfa-8f2f-4b38-9f34-fd1b6ebd63af" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesLeasingArrangements_b8db86e7-93df-4445-b577-462a1197d078" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxLiabilitiesLeasingArrangements"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxLiabilities_88ef99dd-7c6d-42e6-b3d8-bd296c013f08" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesLeasingArrangements_b8db86e7-93df-4445-b577-462a1197d078" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesOtherFiniteLivedAssets_cc82d404-e492-4c8d-b813-4d6d4297140f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxLiabilitiesOtherFiniteLivedAssets"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxLiabilities_88ef99dd-7c6d-42e6-b3d8-bd296c013f08" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesOtherFiniteLivedAssets_cc82d404-e492-4c8d-b813-4d6d4297140f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesPrepaidExpenses_2901d543-1b2c-44ba-8540-5297c271848d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxLiabilitiesPrepaidExpenses"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxLiabilities_88ef99dd-7c6d-42e6-b3d8-bd296c013f08" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesPrepaidExpenses_2901d543-1b2c-44ba-8540-5297c271848d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesOther_5383e720-1762-42cb-8b89-353ac5c2372a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxLiabilitiesOther"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxLiabilities_88ef99dd-7c6d-42e6-b3d8-bd296c013f08" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesOther_5383e720-1762-42cb-8b89-353ac5c2372a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment_589718f7-a5ec-4e0a-8444-abe1ef75def3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxLiabilities_88ef99dd-7c6d-42e6-b3d8-bd296c013f08" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment_589718f7-a5ec-4e0a-8444-abe1ef75def3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_ASC715SupplementalExecutiveRetirementPlanAsset_4460300e-1d09-47cc-9646-262e48b2f742" xlink:href="cass-20241231.xsd#cass_ASC715SupplementalExecutiveRetirementPlanAsset"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxLiabilities_88ef99dd-7c6d-42e6-b3d8-bd296c013f08" xlink:to="loc_cass_ASC715SupplementalExecutiveRetirementPlanAsset_4460300e-1d09-47cc-9646-262e48b2f742" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsLiabilitiesNet_d4581e1f-5d1b-47ff-88fa-84bc9085160c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxAssetsLiabilitiesNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsNet_dd18ac90-6d2c-4af3-9976-68437391af8d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxAssetsNet"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsLiabilitiesNet_d4581e1f-5d1b-47ff-88fa-84bc9085160c" xlink:to="loc_us-gaap_DeferredTaxAssetsNet_dd18ac90-6d2c-4af3-9976-68437391af8d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilities_b08adb63-78b8-4d2a-a443-792eaa9b12f1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredTaxLiabilities"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsLiabilitiesNet_d4581e1f-5d1b-47ff-88fa-84bc9085160c" xlink:to="loc_us-gaap_DeferredTaxLiabilities_b08adb63-78b8-4d2a-a443-792eaa9b12f1" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/DisclosuresaboutFairValueofFinancialInstrumentsSummaryoftheCompanysFinancialInstrumentsDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#DisclosuresaboutFairValueofFinancialInstrumentsSummaryoftheCompanysFinancialInstrumentsDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/DisclosuresaboutFairValueofFinancialInstrumentsSummaryoftheCompanysFinancialInstrumentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure_6007a782-d67a-46fc-9037-ac5e815fbd5b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesFairValueDisclosure"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsFairValueDisclosure_7fb6a92e-eabd-4a84-a391-a8c924464682" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DepositsFairValueDisclosure"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosure_6007a782-d67a-46fc-9037-ac5e815fbd5b" xlink:to="loc_us-gaap_DepositsFairValueDisclosure_7fb6a92e-eabd-4a84-a391-a8c924464682" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableFairValueDisclosure_63b02ced-a29d-40c3-8dc5-b03c717132b7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccountsPayableFairValueDisclosure"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosure_6007a782-d67a-46fc-9037-ac5e815fbd5b" xlink:to="loc_us-gaap_AccountsPayableFairValueDisclosure_63b02ced-a29d-40c3-8dc5-b03c717132b7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedLiabilitiesFairValueDisclosure_d4bda409-2943-434e-b7a1-daa411d03531" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccruedLiabilitiesFairValueDisclosure"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosure_6007a782-d67a-46fc-9037-ac5e815fbd5b" xlink:to="loc_us-gaap_AccruedLiabilitiesFairValueDisclosure_d4bda409-2943-434e-b7a1-daa411d03531" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_30433406-03eb-4309-bec5-43dca52e7dcd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_ad31fc23-202a-4041-bcd6-7311b37d820f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsFairValueDisclosure_30433406-03eb-4309-bec5-43dca52e7dcd" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_ad31fc23-202a-4041-bcd6-7311b37d820f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_7487d66c-1e77-42de-af11-4bff211cb381" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsFairValueDisclosure_30433406-03eb-4309-bec5-43dca52e7dcd" xlink:to="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_7487d66c-1e77-42de-af11-4bff211cb381" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansReceivableFairValueDisclosure_bee94649-55ef-4382-b1ea-8f8187888f9e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LoansReceivableFairValueDisclosure"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsFairValueDisclosure_30433406-03eb-4309-bec5-43dca52e7dcd" xlink:to="loc_us-gaap_LoansReceivableFairValueDisclosure_bee94649-55ef-4382-b1ea-8f8187888f9e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_AccruedInterestReceivableFairValueDisclosure_66cf6fa9-1e40-4c3d-a664-9b78d5758c04" xlink:href="cass-20241231.xsd#cass_AccruedInterestReceivableFairValueDisclosure"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsFairValueDisclosure_30433406-03eb-4309-bec5-43dca52e7dcd" xlink:to="loc_cass_AccruedInterestReceivableFairValueDisclosure_66cf6fa9-1e40-4c3d-a664-9b78d5758c04" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/RevenuefromContractswithCustomersDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#RevenuefromContractswithCustomersDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/RevenuefromContractswithCustomersDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestIncome_164c17f9-6493-4e36-b9e0-07917e528199" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoninterestIncome"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_b19df592-4632-4eef-9b9d-09fa1570ff8c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NoninterestIncome_164c17f9-6493-4e36-b9e0-07917e528199" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_b19df592-4632-4eef-9b9d-09fa1570ff8c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueNotFromContractWithCustomer_7afd8d2d-c525-4a66-84f0-02b21acd6be8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RevenueNotFromContractWithCustomer"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NoninterestIncome_164c17f9-6493-4e36-b9e0-07917e528199" xlink:to="loc_us-gaap_RevenueNotFromContractWithCustomer_7afd8d2d-c525-4a66-84f0-02b21acd6be8" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/LeasesScheduleofoperatingleaseliabilitiesDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#LeasesScheduleofoperatingleaseliabilitiesDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/LeasesScheduleofoperatingleaseliabilitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_f99a5121-2f2f-4973-8d5f-48c39797cdb8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_49c40f85-bf9f-427d-b5fc-9680e05be5fc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_f99a5121-2f2f-4973-8d5f-48c39797cdb8" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_49c40f85-bf9f-427d-b5fc-9680e05be5fc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiability_7b77980f-b567-41ce-b767-90c9ff9161c1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OperatingLeaseLiability"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_f99a5121-2f2f-4973-8d5f-48c39797cdb8" xlink:to="loc_us-gaap_OperatingLeaseLiability_7b77980f-b567-41ce-b767-90c9ff9161c1" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/LeasesScheduleofoperatingleaseliabilitiesDetails_1" xlink:type="simple" xlink:href="cass-20241231.xsd#LeasesScheduleofoperatingleaseliabilitiesDetails_1"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/LeasesScheduleofoperatingleaseliabilitiesDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_fc51725c-4e65-4ee0-a6ef-0468b3ebaaa7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_d3cd6623-b27e-4ad7-969b-e373a5b9519f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_fc51725c-4e65-4ee0-a6ef-0468b3ebaaa7" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_d3cd6623-b27e-4ad7-969b-e373a5b9519f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_69ee504f-9e8a-4bb5-9b72-9e2913be9ea0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_fc51725c-4e65-4ee0-a6ef-0468b3ebaaa7" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_69ee504f-9e8a-4bb5-9b72-9e2913be9ea0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_2f4708ab-cdfd-44fc-964d-56aff648a498" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_fc51725c-4e65-4ee0-a6ef-0468b3ebaaa7" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_2f4708ab-cdfd-44fc-964d-56aff648a498" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_c385ec1f-260c-4bd5-8329-0e0c02c3afb0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_fc51725c-4e65-4ee0-a6ef-0468b3ebaaa7" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_c385ec1f-260c-4bd5-8329-0e0c02c3afb0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_6bf1122b-4911-47a7-bcde-0d654b095e18" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_fc51725c-4e65-4ee0-a6ef-0468b3ebaaa7" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_6bf1122b-4911-47a7-bcde-0d654b095e18" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_LesseeOperatingLeaseLiabilityToBePaidDueAfterYearFour_0732554a-0710-4b62-81e9-f4fab5eeedb1" xlink:href="cass-20241231.xsd#cass_LesseeOperatingLeaseLiabilityToBePaidDueAfterYearFour"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_fc51725c-4e65-4ee0-a6ef-0468b3ebaaa7" xlink:to="loc_cass_LesseeOperatingLeaseLiabilityToBePaidDueAfterYearFour_0732554a-0710-4b62-81e9-f4fab5eeedb1" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/CondensedFinancialInformationofParentCompanyScheduleofCondensedBalanceSheetsDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#CondensedFinancialInformationofParentCompanyScheduleofCondensedBalanceSheetsDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/CondensedFinancialInformationofParentCompanyScheduleofCondensedBalanceSheetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_2df7a93f-ace2-4370-997e-a34da01db069" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Assets"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_PaymentsInAdvanceOfFunding_d27c492b-bd09-46a6-bc9d-745dedbbee5c" xlink:href="cass-20241231.xsd#cass_PaymentsInAdvanceOfFunding"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_2df7a93f-ace2-4370-997e-a34da01db069" xlink:to="loc_cass_PaymentsInAdvanceOfFunding_d27c492b-bd09-46a6-bc9d-745dedbbee5c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReceivablesFromCustomers_22d4da9e-fd2b-4c07-97cd-7a788deb7cee" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReceivablesFromCustomers"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_2df7a93f-ace2-4370-997e-a34da01db069" xlink:to="loc_us-gaap_ReceivablesFromCustomers_22d4da9e-fd2b-4c07-97cd-7a788deb7cee" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures_1cb435da-a6d4-4b05-bb19-9171850f2b11" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_2df7a93f-ace2-4370-997e-a34da01db069" xlink:to="loc_us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures_1cb435da-a6d4-4b05-bb19-9171850f2b11" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_231bdad3-d7ef-4655-968d-5c0719e7cda9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_2df7a93f-ace2-4370-997e-a34da01db069" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_231bdad3-d7ef-4655-968d-5c0719e7cda9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssets_bbc4ac02-3c2c-4041-b44d-e8044c290b01" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherAssets"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_2df7a93f-ace2-4370-997e-a34da01db069" xlink:to="loc_us-gaap_OtherAssets_bbc4ac02-3c2c-4041-b44d-e8044c290b01" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_febd50a0-7265-4a89-a254-a70a6be0c92e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_2df7a93f-ace2-4370-997e-a34da01db069" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_febd50a0-7265-4a89-a254-a70a6be0c92e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_563c15d7-fa65-4ccf-b2c9-a6d3f3037733" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_2df7a93f-ace2-4370-997e-a34da01db069" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_563c15d7-fa65-4ccf-b2c9-a6d3f3037733" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndDueFromBanks_566e2d53-0bde-4c1b-a336-36aae4a9a3d5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashAndDueFromBanks"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_2df7a93f-ace2-4370-997e-a34da01db069" xlink:to="loc_us-gaap_CashAndDueFromBanks_566e2d53-0bde-4c1b-a336-36aae4a9a3d5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermInvestments_ee323f00-9e08-4bb1-865a-e0f6aebab4af" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShortTermInvestments"/>
    <link:calculationArc order="9" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_2df7a93f-ace2-4370-997e-a34da01db069" xlink:to="loc_us-gaap_ShortTermInvestments_ee323f00-9e08-4bb1-865a-e0f6aebab4af" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/CondensedFinancialInformationofParentCompanyScheduleofCondensedStatementofIncomeDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#CondensedFinancialInformationofParentCompanyScheduleofCondensedStatementofIncomeDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/CondensedFinancialInformationofParentCompanyScheduleofCondensedStatementofIncomeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_cass_IncomeBeforeUndistributedIncomeOfSubsidiaries_81432334-849b-4e25-9036-c347fbf4ed06" xlink:href="cass-20241231.xsd#cass_IncomeBeforeUndistributedIncomeOfSubsidiaries"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_550290bc-4cdb-4bd0-8c4f-3d6d0123d254" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_527f4c88-4482-47ca-99d1-ede307100ec9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeLossFromEquityMethodInvestments"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_550290bc-4cdb-4bd0-8c4f-3d6d0123d254" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_527f4c88-4482-47ca-99d1-ede307100ec9" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://cassinfo.com/role/CondensedFinancialInformationofParentCompanyScheduleofStatementsofCashFlowsDetails" xlink:type="simple" xlink:href="cass-20241231.xsd#CondensedFinancialInformationofParentCompanyScheduleofStatementsofCashFlowsDetails"/>
  <link:calculationLink xlink:role="http://cassinfo.com/role/CondensedFinancialInformationofParentCompanyScheduleofStatementsofCashFlowsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_8fd4e979-bb2f-4073-9262-af06b39c2203" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayableAndOtherOperatingLiabilities_069214c2-5fdc-4de9-a488-02eb14075efa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInAccountsPayableAndOtherOperatingLiabilities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_8fd4e979-bb2f-4073-9262-af06b39c2203" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsPayableAndOtherOperatingLiabilities_069214c2-5fdc-4de9-a488-02eb14075efa" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfDividendsCommonStock_b6bbbd22-9c2f-4fc1-a87e-dae353e1874c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsOfDividendsCommonStock"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_8fd4e979-bb2f-4073-9262-af06b39c2203" xlink:to="loc_us-gaap_PaymentsOfDividendsCommonStock_b6bbbd22-9c2f-4fc1-a87e-dae353e1874c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_NetIncreaseDecreaseInAccountsAndDraftsReceivableFromCustomers_4af43b66-d142-4f31-baad-61d9304ea389" xlink:href="cass-20241231.xsd#cass_NetIncreaseDecreaseInAccountsAndDraftsReceivableFromCustomers"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_8fd4e979-bb2f-4073-9262-af06b39c2203" xlink:to="loc_cass_NetIncreaseDecreaseInAccountsAndDraftsReceivableFromCustomers_4af43b66-d142-4f31-baad-61d9304ea389" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_d56e014b-4f22-4458-9c36-4f04148e30a5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_8fd4e979-bb2f-4073-9262-af06b39c2203" xlink:to="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_d56e014b-4f22-4458-9c36-4f04148e30a5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_e4d74f00-9c0e-4da2-aee6-33d9fc471740" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromPaymentsForOtherFinancingActivities"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_8fd4e979-bb2f-4073-9262-af06b39c2203" xlink:to="loc_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_e4d74f00-9c0e-4da2-aee6-33d9fc471740" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_f0d3362b-80a0-4cc5-bd84-aae9c7af1a13" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_b4831b3b-b230-4e0f-9581-250b183dd917" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_f0d3362b-80a0-4cc5-bd84-aae9c7af1a13" xlink:to="loc_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_b4831b3b-b230-4e0f-9581-250b183dd917" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities_0268992a-8b8d-4018-8418-9dbc6eca7878" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_f0d3362b-80a0-4cc5-bd84-aae9c7af1a13" xlink:to="loc_us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities_0268992a-8b8d-4018-8418-9dbc6eca7878" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireLifeInsurancePolicies_3be68276-fbaf-465a-a3de-303762967682" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsToAcquireLifeInsurancePolicies"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_f0d3362b-80a0-4cc5-bd84-aae9c7af1a13" xlink:to="loc_us-gaap_PaymentsToAcquireLifeInsurancePolicies_3be68276-fbaf-465a-a3de-303762967682" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_92c61220-8384-48ec-9a78-6e1ec54ca6ae" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_f0d3362b-80a0-4cc5-bd84-aae9c7af1a13" xlink:to="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_92c61220-8384-48ec-9a78-6e1ec54ca6ae" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt_4256787d-f843-4f39-99dd-87e7dfb3fca0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_f0d3362b-80a0-4cc5-bd84-aae9c7af1a13" xlink:to="loc_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt_4256787d-f843-4f39-99dd-87e7dfb3fca0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cass_IncreaseDecreaseInPaymentsInExcessOfFunding_a79d655a-1be8-4d5a-852d-2a7732215518" xlink:href="cass-20241231.xsd#cass_IncreaseDecreaseInPaymentsInExcessOfFunding"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_f0d3362b-80a0-4cc5-bd84-aae9c7af1a13" xlink:to="loc_cass_IncreaseDecreaseInPaymentsInExcessOfFunding_a79d655a-1be8-4d5a-852d-2a7732215518" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForProceedsFromLoansAndLeases_c1e7c1ed-0ebb-4ad4-a470-3e39b713a1df" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsForProceedsFromLoansAndLeases"/>
    <link:calculationArc order="7" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_f0d3362b-80a0-4cc5-bd84-aae9c7af1a13" xlink:to="loc_us-gaap_PaymentsForProceedsFromLoansAndLeases_c1e7c1ed-0ebb-4ad4-a470-3e39b713a1df" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesGross_6f49cd18-735d-4344-bbaf-71a6cdc7bd77" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsToAcquireBusinessesGross"/>
    <link:calculationArc order="8" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_f0d3362b-80a0-4cc5-bd84-aae9c7af1a13" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesGross_6f49cd18-735d-4344-bbaf-71a6cdc7bd77" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_8ebf57fe-db13-481d-85d9-c109d4e63176" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_931b286e-3509-476a-8a5e-3cbfd6a9eac1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_8ebf57fe-db13-481d-85d9-c109d4e63176" xlink:to="loc_us-gaap_NetIncomeLoss_931b286e-3509-476a-8a5e-3cbfd6a9eac1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_085eaeb7-317e-4e93-93c2-30d8d0748d24" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeLossFromEquityMethodInvestments"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_8ebf57fe-db13-481d-85d9-c109d4e63176" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_085eaeb7-317e-4e93-93c2-30d8d0748d24" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingAssets_ddbad59c-5fcc-4b18-995e-7f961f5f3070" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInOtherOperatingAssets"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_8ebf57fe-db13-481d-85d9-c109d4e63176" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherOperatingAssets_ddbad59c-5fcc-4b18-995e-7f961f5f3070" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_b0303266-2f64-4622-89e3-0ec47a27af3b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncreaseDecreaseInOtherOperatingLiabilities"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_8ebf57fe-db13-481d-85d9-c109d4e63176" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_b0303266-2f64-4622-89e3-0ec47a27af3b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherOperatingActivitiesCashFlowStatement_6e4e1381-ef87-497d-abdd-f616331814c6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherOperatingActivitiesCashFlowStatement"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_8ebf57fe-db13-481d-85d9-c109d4e63176" xlink:to="loc_us-gaap_OtherOperatingActivitiesCashFlowStatement_6e4e1381-ef87-497d-abdd-f616331814c6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_b7159115-791d-4312-8115-ed58ea54a5e7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensation"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_8ebf57fe-db13-481d-85d9-c109d4e63176" xlink:to="loc_us-gaap_ShareBasedCompensation_b7159115-791d-4312-8115-ed58ea54a5e7" xlink:type="arc"/>
  </link:calculationLink>
</link:linkbase>
