-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 MBGQvJO8/m9euSjOmU/C0PCAheozAlhonBtG9gnfHXzqsUck1S4xR4kDjWuCfgvE
 cDuPKFHoOkaHSFPxAqwmtw==

<SEC-DOCUMENT>0001135536-06-000001.txt : 20060103
<SEC-HEADER>0001135536-06-000001.hdr.sgml : 20060102
<ACCEPTANCE-DATETIME>20060103164022
ACCESSION NUMBER:		0001135536-06-000001
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20051221
FILED AS OF DATE:		20060103
DATE AS OF CHANGE:		20060103

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			DELTATHREE INC
		CENTRAL INDEX KEY:			0001086740
		STANDARD INDUSTRIAL CLASSIFICATION:	TELEPHONE COMMUNICATIONS (NO RADIO TELEPHONE) [4813]
		IRS NUMBER:				134006766
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		75 BROAD ST
		STREET 2:		31ST FL
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10004
		BUSINESS PHONE:		2125004850

	MAIL ADDRESS:	
		STREET 1:		75 BROAD ST
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10004

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	DELTATHREE COM INC
		DATE OF NAME CHANGE:	19990519

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BEN-OZER NOAM
		CENTRAL INDEX KEY:			0001135536

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-28063
		FILM NUMBER:		06502960

	BUSINESS ADDRESS:	
		STREET 1:		C/O EQUITY ONE INC
		STREET 2:		1696 NE MIAMI GARDENS DR
		CITY:			N MIAMI
		STATE:			FL
		ZIP:			33179
		BUSINESS PHONE:		3059471664

	MAIL ADDRESS:	
		STREET 1:		1696 NE MIAMI GARDENS DR
		CITY:			N MIAMI
		STATE:			FL
		ZIP:			33179
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-12-21</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001086740</issuerCik>
        <issuerName>DELTATHREE INC</issuerName>
        <issuerTradingSymbol>DDDC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001135536</rptOwnerCik>
            <rptOwnerName>BEN-OZER NOAM</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1696 NE MIAMI GARDENS DR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>N MIAMI</rptOwnerCity>
            <rptOwnerState>FL</rptOwnerState>
            <rptOwnerZipCode>33179</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Option to purchase Common Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>3.02</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-12-21</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2006-12-21</value>
            </exerciseDate>
            <expirationDate>
                <value>2015-12-21</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>10000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>34848</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Options granted to member of board of directors for continuing board service.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Noam Ben-Ozer</signatureName>
        <signatureDate>2005-12-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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