<SEC-DOCUMENT>0001209191-14-046262.txt : 20140707
<SEC-HEADER>0001209191-14-046262.hdr.sgml : 20140707
<ACCEPTANCE-DATETIME>20140707175941
ACCESSION NUMBER:		0001209191-14-046262
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20140703
FILED AS OF DATE:		20140707
DATE AS OF CHANGE:		20140707

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			K12 INC
		CENTRAL INDEX KEY:			0001157408
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-EDUCATIONAL SERVICES [8200]
		IRS NUMBER:				954774688
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		2300 CORPORATE PARK DRIVE
		STREET 2:		SUITE 200
		CITY:			HERNDON
		STATE:			VA
		ZIP:			20171
		BUSINESS PHONE:		7034837000

	MAIL ADDRESS:	
		STREET 1:		2300 CORPORATE PARK DRIVE
		STREET 2:		SUITE 200
		CITY:			HERNDON
		STATE:			VA
		ZIP:			20171

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DAVIS NATHANIEL A
		CENTRAL INDEX KEY:			0001259955

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33883
		FILM NUMBER:		14963792

	MAIL ADDRESS:	
		STREET 1:		1500 ECKINGTON PLACE NE
		CITY:			WASHINGTON
		STATE:			DC
		ZIP:			20002
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2014-07-03</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001157408</issuerCik>
        <issuerName>K12 INC</issuerName>
        <issuerTradingSymbol>LRN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001259955</rptOwnerCik>
            <rptOwnerName>DAVIS NATHANIEL A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2300 CORPORATE PARK DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>HERNDON</rptOwnerCity>
            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>20171</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman and CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2014-07-03</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>8348</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>23.75</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>239037</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents the number of shares withheld by the Company upon the vesting of restricted shares to cover the executive's withholding tax on income associated with the satisfaction of all vesting conditions. The number of shares withheld is based upon the closing price of a share of K12 common stock on the last day the New York Stock Exchange was open prior to the vesting date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ John C. Grothaus, attorney-in-fact</signatureName>
        <signatureDate>2014-07-07</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
