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  <xs:element id="nmih_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlansNetofSharesForTaxWithholdings" abstract="false" name="StockIssuedDuringPeriodSharesEmployeeStockPurchasePlansNetofSharesForTaxWithholdings" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="nmih_ClassOfWarrantOrRightWarrantsExpiredUnexercisedResultingInGainLossDuringPeriod" abstract="false" name="ClassOfWarrantOrRightWarrantsExpiredUnexercisedResultingInGainLossDuringPeriod" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmih_ReinsuranceRetentionPolicyCededAggregatePremiums" abstract="false" name="ReinsuranceRetentionPolicyCededAggregatePremiums" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmih_ReinsuranceRetentionRiskPremiumsPaid" abstract="false" name="ReinsuranceRetentionRiskPremiumsPaid" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmih_NumberOfOperatingLeasesCorporateOfficeAndDataCenterFacility" abstract="false" name="NumberOfOperatingLeasesCorporateOfficeAndDataCenterFacility" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="nmih_SeniorSecuredTermLoan2018Member" abstract="true" name="SeniorSecuredTermLoan2018Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmih_CorporateHeadquartersMember" abstract="true" name="CorporateHeadquartersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmih_NumberOfReinsuranceEngagementsTerminated" abstract="false" name="NumberOfReinsuranceEngagementsTerminated" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="nmih_DebtSecuritiesCorporateComponentOfTotal.Percentage" abstract="false" name="DebtSecuritiesCorporateComponentOfTotal.Percentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nmih_GainLossonChangeinFairValueofWarrantLiability" abstract="false" name="GainLossonChangeinFairValueofWarrantLiability" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmih_DebtInstrumentCovenantTermsDebtToTotalCapitalizationRatioMaximum" abstract="false" name="DebtInstrumentCovenantTermsDebtToTotalCapitalizationRatioMaximum" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nmih_LoansInPoolPastDue60DaysOrMoreNumberOfLoans" abstract="false" name="LoansInPoolPastDue60DaysOrMoreNumberOfLoans" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="nmih_PreviouslyCededPrimaryRiskInForceRecaptured" abstract="false" name="PreviouslyCededPrimaryRiskInForceRecaptured" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmih_CurrentFirstLayerRetainedLoss" abstract="false" name="CurrentFirstLayerRetainedLoss" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmih_LiabilityforUnpaidClaimsandClaimsAdjustmentExpenseClaimsPaidIncludingAmountsCoveredByInsurance" abstract="false" name="LiabilityforUnpaidClaimsandClaimsAdjustmentExpenseClaimsPaidIncludingAmountsCoveredByInsurance" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmih_PriorYearClaimsAndClaimsAdjustmentExpenseCaseReserves" abstract="false" name="PriorYearClaimsAndClaimsAdjustmentExpenseCaseReserves" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmih_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredButNotReportedIBNRClaimsNumberOfPrimaryLoansInDefaultPercentOfTotalPoliciesInForce" abstract="false" name="LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredButNotReportedIBNRClaimsNumberOfPrimaryLoansInDefaultPercentOfTotalPoliciesInForce" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nmih_EarningsPerShareBasicAndDilutedEPSAbstract" abstract="true" name="EarningsPerShareBasicAndDilutedEPSAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="nmih_ReinsuranceAgreementOptionalTerminationRightPercentOfReinsuranceCoverageThreshold" abstract="false" name="ReinsuranceAgreementOptionalTerminationRightPercentOfReinsuranceCoverageThreshold" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nmih_ThirdPartyReinsurersMember" abstract="true" name="ThirdPartyReinsurersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmih_ReinsuranceProfitCommission" abstract="false" name="ReinsuranceProfitCommission" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmih_FinancialIndustryGroupMember" abstract="true" name="FinancialIndustryGroupMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
