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  <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_SecuredRevolvingCreditFacility2021Member" abstract="true" name="SecuredRevolvingCreditFacility2021Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_ClassofWarrantorRightNumberofWarrantsExercisedDuringPeriod" abstract="false" name="ClassofWarrantorRightNumberofWarrantsExercisedDuringPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="nmih_WarrantLiability" abstract="false" name="WarrantLiability" nillable="true" xbrli:periodType="instant" 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:element id="nmih_EligiblePoliciesPoolFourMember" abstract="true" name="EligiblePoliciesPoolFourMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmih_ReinsuranceRetentionPolicyTermOfUnderlyingMortgageAmortization" abstract="false" name="ReinsuranceRetentionPolicyTermOfUnderlyingMortgageAmortization" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="nmih_FannieMaeMember" abstract="true" name="FannieMaeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmih_EligiblePoliciesPoolTwoMember" abstract="true" name="EligiblePoliciesPoolTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_CededCreditRiskCommissionEarnedPercentage" abstract="false" name="CededCreditRiskCommissionEarnedPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <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_ReinsuranceCedingCommissionEarned" abstract="false" name="ReinsuranceCedingCommissionEarned" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmih_A2021QSRTransactionMember" abstract="true" name="A2021QSRTransactionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmih_ReinsuranceRetentionPolicyExcessRetentionSecondLayerAmountReinsured" abstract="false" name="ReinsuranceRetentionPolicyExcessRetentionSecondLayerAmountReinsured" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmih_EligiblePoliciesPoolNineMember" abstract="true" name="EligiblePoliciesPoolNineMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmih_DebtInstrumentVariableInterestRateFloor" abstract="false" name="DebtInstrumentVariableInterestRateFloor" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nmih_DebtInstrumentRedemptionPricePercentageOfPrincipalAmountRedeemable" abstract="false" name="DebtInstrumentRedemptionPricePercentageOfPrincipalAmountRedeemable" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nmih_LesseeOperatingLeaseLiabilityPaymentsDueYearSix" abstract="false" name="LesseeOperatingLeaseLiabilityPaymentsDueYearSix" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmih_TwoThousandSeventeenILNTransactionMember" abstract="true" name="TwoThousandSeventeenILNTransactionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmih_StatutoryAccountingPracticesContingencyReserve" abstract="false" name="StatutoryAccountingPracticesContingencyReserve" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmih_LoansInPoolLoanToValueRatio" abstract="false" name="LoansInPoolLoanToValueRatio" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="nmih_InvestmentsClassifiedByIssuerIndustryGroupTableTextBlock" abstract="false" name="InvestmentsClassifiedByIssuerIndustryGroupTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="nmih_EligiblePoliciesPoolEightMember" abstract="true" name="EligiblePoliciesPoolEightMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmih_DebtSecuritiesByIndustryAxis" abstract="true" name="DebtSecuritiesByIndustryAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="nmih_StatutoryAccountingPracticesStatutoryCapitalAndSurplusIncludingContingencyReserve" abstract="false" name="StatutoryAccountingPracticesStatutoryCapitalAndSurplusIncludingContingencyReserve" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmih_ILNTransactionsMember" abstract="true" name="ILNTransactionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmih_EligiblePoliciesPoolSixMember" abstract="true" name="EligiblePoliciesPoolSixMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmih_IndustrialIndustryGroupMember" abstract="true" name="IndustrialIndustryGroupMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmih_EligiblePoliciesPoolSevenMember" abstract="true" name="EligiblePoliciesPoolSevenMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmih_DebtInstrumentCovenantTermsDebtToTotalCapitalizationRatioMaximum" abstract="false" name="DebtInstrumentCovenantTermsDebtToTotalCapitalizationRatioMaximum" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
</xs:schema>
