<SEC-DOCUMENT>0001080997-21-000003.txt : 20210317
<SEC-HEADER>0001080997-21-000003.hdr.sgml : 20210317
<ACCEPTANCE-DATETIME>20210317211452
ACCESSION NUMBER:		0001080997-21-000003
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210315
FILED AS OF DATE:		20210317
DATE AS OF CHANGE:		20210317

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MILLS THOMAS E IV
		CENTRAL INDEX KEY:			0001080997

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34460
		FILM NUMBER:		21752715

	MAIL ADDRESS:	
		STREET 1:		10680 TREENA STREET, SUITE 600
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92131

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			KRATOS DEFENSE & SECURITY SOLUTIONS, INC.
		CENTRAL INDEX KEY:			0001069258
		STANDARD INDUSTRIAL CLASSIFICATION:	GUIDED MISSILES & SPACE VEHICLES & PARTS [3760]
		IRS NUMBER:				133818604
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1227

	BUSINESS ADDRESS:	
		STREET 1:		10680 TREENA STREET
		STREET 2:		SUITE 600
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92131
		BUSINESS PHONE:		858-812-7300

	MAIL ADDRESS:	
		STREET 1:		10680 TREENA STREET
		STREET 2:		SUITE 600
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92131

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	WIRELESS FACILITIES INC
		DATE OF NAME CHANGE:	19990817
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-03-15</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001069258</issuerCik>
        <issuerName>KRATOS DEFENSE &amp; SECURITY SOLUTIONS, INC.</issuerName>
        <issuerTradingSymbol>KTOS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001080997</rptOwnerCik>
            <rptOwnerName>MILLS THOMAS E IV</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>10680 TREENA STREET, SUITE 600</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SAN DIEGO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92131</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President, C5ISR Div.</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-03-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>11135</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>25.09</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>40857</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Shares withheld in a net transaction to satisfy the minimum tax liability, in accordance with Issuer's trading policies, in connection with shares vested March 4, 2021 from performance restricted stock units granted in 2018 as reported on a Form 4 filed March 8, 2021 and released March 15, 2021.</footnote>
        <footnote id="F2">Includes approximately 9,388 shares held through Issuer's 401(k) Plan.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Thomas E. Mills, by Eva Yee, Attorney-In-Fact</signatureName>
        <signatureDate>2021-03-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
