-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 AadJiZknx4XETNlql+X/nhthDe52L8zT51TlVr1fY9dArghxps1T1JKxvWMyh2UQ
 5qG6Za4gQ70gSKscIStX/g==

<SEC-DOCUMENT>0001267306-08-000035.txt : 20080516
<SEC-HEADER>0001267306-08-000035.hdr.sgml : 20080516
<ACCEPTANCE-DATETIME>20080516094337
ACCESSION NUMBER:		0001267306-08-000035
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080515
FILED AS OF DATE:		20080516
DATE AS OF CHANGE:		20080516

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NYMAGIC INC
		CENTRAL INDEX KEY:			0000847431
		STANDARD INDUSTRIAL CLASSIFICATION:	SURETY INSURANCE [6351]
		IRS NUMBER:				133534162
		STATE OF INCORPORATION:			NY
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		919 THIRD AVENUE, 10TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
		BUSINESS PHONE:		2125510600

	MAIL ADDRESS:	
		STREET 1:		919 THIRD AVENUE, 10TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MICHAELCHECK WILLIAM JETER
		CENTRAL INDEX KEY:			0001192833

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-11238
		FILM NUMBER:		08840469

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		2125510600

	MAIL ADDRESS:	
		STREET 1:		C/O NYMAGIC INC
		STREET 2:		919 THIRD AVENUE, 10TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
</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>2008-05-15</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000847431</issuerCik>
        <issuerName>NYMAGIC INC</issuerName>
        <issuerTradingSymbol>NYM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001192833</rptOwnerCik>
            <rptOwnerName>MICHAELCHECK WILLIAM JETER</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O NYMAGIC INC</rptOwnerStreet1>
            <rptOwnerStreet2>919 THIRD AVENUE, 10TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10022</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-05-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>12800</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>21.9783</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>225126</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <ownerSignature>
        <signatureName>Paul J. Hart, Attorney-in-Fact</signatureName>
        <signatureDate>2008-05-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----