<?xml version="1.0" encoding="utf-8"?>
<!--Generated by DFIN XBRL Instance Document - http://www.dfinsolutions.com/ - Version R3.0 - on 09-May-2024 [05:01:21] {PM}-->
<linkbase xmlns="http://www.xbrl.org/2003/linkbase" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
<roleRef xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedLabel" roleURI="http://www.xbrl.org/2009/role/negatedLabel" />
<roleRef xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodEndLabel" roleURI="http://www.xbrl.org/2009/role/negatedPeriodEndLabel" />
<roleRef xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodStartLabel" roleURI="http://www.xbrl.org/2009/role/negatedPeriodStartLabel" />
<roleRef xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTotalLabel" roleURI="http://www.xbrl.org/2009/role/negatedTotalLabel" />
<roleRef xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedNetLabel" roleURI="http://www.xbrl.org/2009/role/negatedNetLabel" />
<roleRef xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTerseLabel" roleURI="http://www.xbrl.org/2009/role/negatedTerseLabel" />
<roleRef xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd#netLabel" roleURI="http://www.xbrl.org/2009/role/netLabel" />
<labelLink xlink:type="extended" xlink:role="http://www.xbrl.org/2003/role/link">
<loc xlink:type="locator" xlink:href="ck0001513363-20240508.xsd#ck0001513363_RiskFactorsMember" xlink:label="loc_ck0001513363_RiskFactorsMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001513363_RiskFactorsMember" xml:lang="en-US">Risk Factors [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001513363_RiskFactorsMember" xlink:to="lab_ck0001513363_RiskFactorsMember" />
<loc xlink:type="locator" xlink:href="ck0001513363-20240508.xsd#ck0001513363_CommonSharesMember" xlink:label="loc_ck0001513363_CommonSharesMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001513363_CommonSharesMember" xml:lang="en-US">Common Shares [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001513363_CommonSharesMember" xlink:to="lab_ck0001513363_CommonSharesMember" />
<loc xlink:type="locator" xlink:href="ck0001513363-20240508.xsd#ck0001513363_CreditFacilityMember" xlink:label="loc_ck0001513363_CreditFacilityMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001513363_CreditFacilityMember" xml:lang="en-US">Credit Facility [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001513363_CreditFacilityMember" xlink:to="lab_ck0001513363_CreditFacilityMember" />
<loc xlink:type="locator" xlink:href="ck0001513363-20240508.xsd#ck0001513363_January2026NotesMember" xlink:label="loc_ck0001513363_January2026NotesMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001513363_January2026NotesMember" xml:lang="en-US">January 2026 Notes [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001513363_January2026NotesMember" xlink:to="lab_ck0001513363_January2026NotesMember" />
<loc xlink:type="locator" xlink:href="ck0001513363-20240508.xsd#ck0001513363_NotesMember" xlink:label="loc_ck0001513363_NotesMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001513363_NotesMember" xml:lang="en-US">Notes [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001513363_NotesMember" xlink:to="lab_ck0001513363_NotesMember" />
<loc xlink:type="locator" xlink:href="ck0001513363-20240508.xsd#ck0001513363_November2026NotesMember" xlink:label="loc_ck0001513363_November2026NotesMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001513363_November2026NotesMember" xml:lang="en-US">November 2026 Notes [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001513363_November2026NotesMember" xlink:to="lab_ck0001513363_November2026NotesMember" />
<loc xlink:type="locator" xlink:href="ck0001513363-20240508.xsd#ck0001513363_OnA1000InvestmentAssumingA5AnnualReturnMember" xlink:label="loc_ck0001513363_OnA1000InvestmentAssumingA5AnnualReturnMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001513363_OnA1000InvestmentAssumingA5AnnualReturnMember" xml:lang="en-US">On A1000 Investment Assuming A5 Annual Return [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001513363_OnA1000InvestmentAssumingA5AnnualReturnMember" xlink:to="lab_ck0001513363_OnA1000InvestmentAssumingA5AnnualReturnMember" />
<loc xlink:type="locator" xlink:href="ck0001513363-20240508.xsd#ck0001513363_OnA1000InvestmentAssumingA5AnnualReturnResultingEntirelyFromNetRealizedCapitalGainsMember" xlink:label="loc_ck0001513363_OnA1000InvestmentAssumingA5AnnualReturnResultingEntirelyFromNetRealizedCapitalGainsMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001513363_OnA1000InvestmentAssumingA5AnnualReturnResultingEntirelyFromNetRealizedCapitalGainsMember" xml:lang="en-US">On A1000 Investment Assuming A5 Annual Return Resulting Entirely From Net Realized Capital Gains [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001513363_OnA1000InvestmentAssumingA5AnnualReturnResultingEntirelyFromNetRealizedCapitalGainsMember" xlink:to="lab_ck0001513363_OnA1000InvestmentAssumingA5AnnualReturnResultingEntirelyFromNetRealizedCapitalGainsMember" />
<loc xlink:type="locator" xlink:href="ck0001513363-20240508.xsd#ck0001513363_SbaDebenturesMember" xlink:label="loc_ck0001513363_SbaDebenturesMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001513363_SbaDebenturesMember" xml:lang="en-US">SBA debentures [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001513363_SbaDebenturesMember" xlink:to="lab_ck0001513363_SbaDebenturesMember" />
<loc xlink:type="locator" xlink:href="ck0001513363-20240508.xsd#ck0001513363_SecuredBorrowingsMember" xlink:label="loc_ck0001513363_SecuredBorrowingsMember" />
<label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_ck0001513363_SecuredBorrowingsMember" xml:lang="en-US">Secured Borrowings [Member]</label>
<labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001513363_SecuredBorrowingsMember" xlink:to="lab_ck0001513363_SecuredBorrowingsMember" />
</labelLink>
</linkbase>
