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  <xsd:element abstract="true" id="sbsi_NonqualifiedStockOptionsMember" name="NonqualifiedStockOptionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_OmniAmericanBancorpInc.Member" name="OmniAmericanBancorpInc.Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_OtherStocksAndBondsMember" name="OtherStocksAndBondsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_PassWatchMember" name="PassWatchMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_RangeOneMember" name="RangeOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_ReceivableImpairedMember" name="ReceivableImpairedMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_RestrictedStockUnitsOutstandingAbstract" name="RestrictedStockUnitsOutstandingAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_ScheduleOfAllowanceForLoanLossesAllowanceBalanceByImpairmentMethodLineItems" name="ScheduleOfAllowanceForLoanLossesAllowanceBalanceByImpairmentMethodLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_ScheduleOfAllowanceForLoanLossesAllowanceBalanceByImpairmentMethodTable" name="ScheduleOfAllowanceForLoanLossesAllowanceBalanceByImpairmentMethodTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_ScheduleOfAllowanceForLoanLossesLoanBalanceByImpairmentMethodLineItems" name="ScheduleOfAllowanceForLoanLossesLoanBalanceByImpairmentMethodLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_ScheduleOfAllowanceForLoanLossesLoanBalanceByImpairmentMethodTable" name="ScheduleOfAllowanceForLoanLossesLoanBalanceByImpairmentMethodTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_ScheduleOfAvailableForSaleAndHeldToMaturitySecuritiesLineItems" name="ScheduleOfAvailableForSaleAndHeldToMaturitySecuritiesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_ScheduleOfAvailableForSaleAndHeldToMaturitySecuritiesTable" name="ScheduleOfAvailableForSaleAndHeldToMaturitySecuritiesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="sbsi_SecuritiesTransferredFromAvailableForSaleToHeldToMaturity" name="SecuritiesTransferredFromAvailableForSaleToHeldToMaturity" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="sbsi_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpiredWeightedAverageGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpiredWeightedAverageGrantDateFairValue" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="sbsi_ShareBasedCompensationArrangementByShareBasedPaymentAwardExpiredInPeriodNumberOfSharesAvailableForGrant" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardExpiredInPeriodNumberOfSharesAvailableForGrant" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="sbsi_ShareBasedCompensationArrangementByShareBasedPaymentAwardGrantedInPeriodNumberOfSharesAvailableForGrant" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardGrantedInPeriodNumberOfSharesAvailableForGrant" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="sbsi_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsVested" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsVested" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="sbsi_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantForfeited" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantForfeited" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="sbsi_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisedInPeriodWeightedAverageGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisedInPeriodWeightedAverageGrantDateFairValue" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="sbsi_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageGrantDateFairValue" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="sbsi_ShareBasedCompensationArrangementByShareBasedPaymentAwardStockAwardsVestedInPeriodNumberOfSharesAvailableForGrant" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardStockAwardsVestedInPeriodNumberOfSharesAvailableForGrant" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="sbsi_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageGrantDateFairValue" name="ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageGrantDateFairValue" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOptionsExercisableAbstract" name="ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOptionsExercisableAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOptionsOutstandingAbstract" name="ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOptionsOutstandingAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_ShareBasedIncentivePlansAbstract" name="ShareBasedIncentivePlansAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_SharesAvailableForGrantAbstract" name="SharesAvailableForGrantAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_SouthsideStatutoryTrustIiiMember" name="SouthsideStatutoryTrustIiiMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_SouthsideStatutoryTrustIvMember" name="SouthsideStatutoryTrustIvMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_SouthsideStatutoryTrustVMember" name="SouthsideStatutoryTrustVMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="sbsi_SpecificallyReservedLoansOrLoanRelationshipsThreshold" name="SpecificallyReservedLoansOrLoanRelationshipsThreshold" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="sbsi_StockDividendsPercentageOfCommonStock" name="StockDividendsPercentageOfCommonStock" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_StockOptionsOutstandingAbstract" name="StockOptionsOutstandingAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="sbsi_SummaryOfImpairedLoansByClassOfLoansForPeriodTableTextBlock" name="SummaryOfImpairedLoansByClassOfLoansForPeriodTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="sbsi_SummaryOfImpairedLoansPrimarilyNonaccrualLoansTableTextBlock" name="SummaryOfImpairedLoansPrimarilyNonaccrualLoansTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="sbsi_SummaryOfNonperformingAssetsForPeriodTableTextBlock" name="SummaryOfNonperformingAssetsForPeriodTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_ThreeYearVestingScheduleMember" name="ThreeYearVestingScheduleMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_TotalGainsLossesMember" name="TotalGainsLossesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sbsi_TotalGainsOrLossesRealizedAndUnrealizedAbstract" name="TotalGainsOrLossesRealizedAndUnrealizedAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="sbsi_TotalHeldToMaturitiesDebtMaturitiesByDateAndMaturityDate" name="TotalHeldToMaturitiesDebtMaturitiesByDateAndMaturityDate" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="sbsi_TrustPreferredSecuritiesAbstract" name="TrustPreferredSecuritiesAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="sbsi_TrustPreferredSecuritiesAmortizedCost" name="TrustPreferredSecuritiesAmortizedCost" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="sbsi_UnsettledIssuancesofBrokeredCDs" name="UnsettledIssuancesofBrokeredCDs" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="sbsi_UnsettledTradesToPurchaseSecuritiesLiability" name="UnsettledTradesToPurchaseSecuritiesLiability" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="sbsi_UnsettledTradesToSellSecurities" name="UnsettledTradesToSellSecurities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="sbsi_WritedownCarryAmountPooledTrustPreferredSecuritiesRecognizedInEarnings" name="WritedownCarryAmountPooledTrustPreferredSecuritiesRecognizedInEarnings" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
</xsd:schema>


