-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 P4sQQ8echtHr0aG4XvzS7Bjz0DXZI4zifS0EgrjkBbi90uIc0U0dGAcdjcGHv7PS
 WTZfznVaQZjh7wQS6OhY0g==

<SEC-DOCUMENT>0001253462-10-000003.txt : 20100406
<SEC-HEADER>0001253462-10-000003.hdr.sgml : 20100406
<ACCEPTANCE-DATETIME>20100406174320
ACCESSION NUMBER:		0001253462-10-000003
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100405
FILED AS OF DATE:		20100406
DATE AS OF CHANGE:		20100406

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BERTHELOT BARRY F
		CENTRAL INDEX KEY:			0001486328

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-25756
		FILM NUMBER:		10735239

	MAIL ADDRESS:	
		STREET 1:		200 WEST CONGRESS STREET
		CITY:			LAFAYETTE
		STATE:			LA
		ZIP:			70501

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			IBERIABANK CORP
		CENTRAL INDEX KEY:			0000933141
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		IRS NUMBER:				721280718
		STATE OF INCORPORATION:			LA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		200 WEST CONGRESS STREET
		CITY:			LAFAYETTE
		STATE:			LA
		ZIP:			70505
		BUSINESS PHONE:		3375214003

	MAIL ADDRESS:	
		STREET 1:		200 WEST CONGRESS STREET
		CITY:			LAFAYETTE
		STATE:			LA
		ZIP:			70505

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ISB FINANCIAL CORP/LA
		DATE OF NAME CHANGE:	19941123
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-04-05</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000933141</issuerCik>
        <issuerName>IBERIABANK CORP</issuerName>
        <issuerTradingSymbol>IBKC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001486328</rptOwnerCik>
            <rptOwnerName>BERTHELOT BARRY F</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>200 WEST CONGRESS STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LAFAYETTE</rptOwnerCity>
            <rptOwnerState>LA</rptOwnerState>
            <rptOwnerZipCode>70501</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EXECUTIVE VICE PRESIDENT</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>COMMON STOCK</value>
            </securityTitle>
            <transactionDate>
                <value>2010-04-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>60.46</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>STOCK OPTIONS</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>60.46</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-04-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2500</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>60.46</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2011-04-05</value>
            </exerciseDate>
            <expirationDate>
                <value>2020-04-05</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>COMMON STOCK</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2500</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>PHANTOM STOCK</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>60.46</value>
                <footnoteId id="F3"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-04-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1040</value>
                    <footnoteId id="F4"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>60.46</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F5"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F5"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>COMMON STOCK</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1040</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">GRANTS OF RESTRICTED STOCK AWARDS VIA ISSUER'S 2010 PLAN, WILL VEST EQUALLY OVER A 7-YEAR PERIOD COMMENCING WITH THE FIRST ANNIVERSARY OF THE DATE OF THE GRANT.</footnote>
        <footnote id="F2">STOCK OPTIONS, AWARDED VIA ISSUER'S 2010 PLAN, WILL VEST OVER A 7-YEAR PERIOD COMMENCING ON THE FIRST ANNIVERSARY OF THE DATE OF GRANT AT ONE SEVENTH PER YEAR.</footnote>
        <footnote id="F3">EACH SHARE OF PHANTOM STOCK REPRESENTS THE RIGHT TO RECEIVE THE CASH VALUE OF ONE SHARE OF IBKC COMMON STOCK.</footnote>
        <footnote id="F4">SHARES OF PHANTOM STOCK ARE PAYABLE IN CASH UPON THE EARLIER OF SCHEDULED DISTRIBUTION DATE(S) OR TERMINATION OF THE REPORTING PERSON'S EMPLOYMENT WITH IBKC.  THE REPORTING PERSON MAY TRANSFER HIS PHANTOM STOCK ACCOUNT INTO AN ALTERNATIVE INVESTMENT ACCOUNT AT ANY TIME.</footnote>
        <footnote id="F5">GRANT OF PHANTOM STOCK AWARDED UNDER ISSUER'S DEFERRED COMPENSATION PLAN, WILL VEST EQUALLY OVER A 6-YEAR PERIOD COMMENCING WITH THE SECOND ANNIVERSARY OF THE DATE OF THE AWARD.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>BARRY F. BERTHELOT</signatureName>
        <signatureDate>2010-04-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----