-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 AwCxmDgVolWrW/5zHbhymywi4hCVt9IFb3Kv30PhckQ2rhEbcKUh23OQHg8TtoWR
 EaLbuwvE+9T4UcPrbRL+Dw==

<SEC-DOCUMENT>0001181431-06-018800.txt : 20060317
<SEC-HEADER>0001181431-06-018800.hdr.sgml : 20060317
<ACCEPTANCE-DATETIME>20060317173925
ACCESSION NUMBER:		0001181431-06-018800
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060316
FILED AS OF DATE:		20060317
DATE AS OF CHANGE:		20060317

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NICOR INC
		CENTRAL INDEX KEY:			0000072020
		STANDARD INDUSTRIAL CLASSIFICATION:	NATURAL GAS DISTRIBUTION [4924]
		IRS NUMBER:				362855175
		STATE OF INCORPORATION:			IL
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1844 FERRY RD
		CITY:			NAPERVILLE
		STATE:			IL
		ZIP:			60563
		BUSINESS PHONE:		6303059500

	MAIL ADDRESS:	
		STREET 1:		PO BOX 3014
		CITY:			NAPERVILLE
		STATE:			IL
		ZIP:			60566-7014

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			COLALILLO CLAUDIA J
		CENTRAL INDEX KEY:			0001205609

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-07297
		FILM NUMBER:		06697020

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		6303059500

	MAIL ADDRESS:	
		STREET 1:		C/O NICOR GAS
		STREET 2:		P O BOX 3014
		CITY:			NAPERVILLE
		STATE:			IL
		ZIP:			60566-7014
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>rrd111674.xml
<DESCRIPTION>RESTRICTED STOCK
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-03-16</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000072020</issuerCik>
        <issuerName>NICOR INC</issuerName>
        <issuerTradingSymbol>GAS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001205609</rptOwnerCik>
            <rptOwnerName>COLALILLO CLAUDIA J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>NICOR INC.</rptOwnerStreet1>
            <rptOwnerStreet2>1844 FERRY ROAD</rptOwnerStreet2>
            <rptOwnerCity>NAPERVILLE</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60563</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-03-16</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2020</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6660.473</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Includes 27.132 shares of common stock acquired in February 2006 under the Dividend Reinvestment Plan.</footnote>
        <footnote id="F2">Includes 30 shares of common stock acquired in March 2006 under the Employee Stock Purchase Plan.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Antoinette M. Lambert,  Attorney-in-Fact</signatureName>
        <signatureDate>2006-03-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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