<SEC-DOCUMENT>0001023731-18-000027.txt : 20180813
<SEC-HEADER>0001023731-18-000027.hdr.sgml : 20180813
<ACCEPTANCE-DATETIME>20180813170736
ACCESSION NUMBER:		0001023731-18-000027
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180810
FILED AS OF DATE:		20180813
DATE AS OF CHANGE:		20180813

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Singh Jaswinder Pal
		CENTRAL INDEX KEY:			0001590497

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38312
		FILM NUMBER:		181013269

	MAIL ADDRESS:	
		STREET 1:		C/O 8X8, INC.
		STREET 2:		2125 O'NEL DRIVE
		CITY:			SAN JOSE
		STATE:			CA
		ZIP:			95131

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			8X8 INC /DE/
		CENTRAL INDEX KEY:			0001023731
		STANDARD INDUSTRIAL CLASSIFICATION:	TELEPHONE COMMUNICATIONS (NO RADIO TELEPHONE) [4813]
		IRS NUMBER:				770142404
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		2125 O'NEL DRIVE
		CITY:			SAN JOSE
		STATE:			CA
		ZIP:			95131
		BUSINESS PHONE:		4087271885

	MAIL ADDRESS:	
		STREET 1:		2125 O'NEL DRIVE
		CITY:			SAN JOSE
		STATE:			CA
		ZIP:			95131

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	NETERGY NETWORKS INC
		DATE OF NAME CHANGE:	20000912

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	8X8 INC
		DATE OF NAME CHANGE:	19961023
</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>2018-08-10</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001023731</issuerCik>
        <issuerName>8X8 INC /DE/</issuerName>
        <issuerTradingSymbol>EGHT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001590497</rptOwnerCik>
            <rptOwnerName>Singh Jaswinder Pal</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O 8X8, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>2125 O'NEL DRIVE</rptOwnerStreet2>
            <rptOwnerCity>SAN JOSE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95131</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-08-10</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>13409</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>22.4</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>71697</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Unit</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2018-08-10</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>13409</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2018-08-10</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>13409</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8328</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each restricted stock unit represents a contingent right to receive one share of EGHT common stock.</footnote>
        <footnote id="F2">Award shall vest as to 100% of the shares subject to the award on the later of (a) the date of the director's completion of Board service and (b) 12 months from the date of grant of such award, in each case subject to the director's completion of Board service.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Scott Pinkerton as attorney-in-fact for Jaswinder Pal Singh</signatureName>
        <signatureDate>2018-08-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
