<SEC-DOCUMENT>0001509409-21-000005.txt : 20210317
<SEC-HEADER>0001509409-21-000005.hdr.sgml : 20210317
<ACCEPTANCE-DATETIME>20210317204454
ACCESSION NUMBER:		0001509409-21-000005
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:			Carrai Phillip D
		CENTRAL INDEX KEY:			0001509409

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34460
		FILM NUMBER:		21752637

	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>0001509409</rptOwnerCik>
            <rptOwnerName>Carrai Phillip D</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, STC Division</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>33825</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>25.09</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>136130</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-03-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F2"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1363</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>26.45</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>134767</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>46644</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by trust</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </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">This transaction was effected pursuant to a 10b5-1 trading plan adopted by the reporting person.</footnote>
        <footnote id="F3">Includes 11,845 shares purchased through Issuer's Employee Stock Purchase Plan and approximately 919 shares held through Issuer's 401(k) Plan.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Phillip D. Carrai, by Eva Yee, Attorney-In-Fact</signatureName>
        <signatureDate>2021-03-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
