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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 LhkDEefRs0H5YKExXaGdA1YFCJs96FncAxR6cjwf0FDPFPMrh6v1DlrIw6LtwZJn
 o4mfrsaZZlWaOxDqE8xL9A==

<SEC-DOCUMENT>9999999995-10-003376.txt : 20101126
<SEC-HEADER>9999999995-10-003376.hdr.sgml : 20101125
<ACCEPTANCE-DATETIME>20101126001512
ACCESSION NUMBER:		9999999995-10-003376
CONFORMED SUBMISSION TYPE:	EFFECT
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20101124
DATE AS OF CHANGE:		20101126
EFFECTIVENESS DATE:		20101124

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			INTERSTATE POWER & LIGHT CO
		CENTRAL INDEX KEY:			0000052485
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC & OTHER SERVICES COMBINED [4931]
		IRS NUMBER:				420331370
		STATE OF INCORPORATION:			IA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		EFFECT
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-170631
		FILM NUMBER:		101216120

	BUSINESS ADDRESS:	
		STREET 1:		200 FIRST ST SE
		STREET 2:		ALLIANT ENERGY TOWER
		CITY:			CEDAR RAPIDS
		STATE:			IA
		ZIP:			52401
		BUSINESS PHONE:		3193984411

	MAIL ADDRESS:	
		STREET 1:		200 FIRST ST SE
		STREET 2:		ALLIANT ENERGY TOWER
		CITY:			CEDAR RAPIDS
		STATE:			IA
		ZIP:			52401

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	IES UTILITIES INC
		DATE OF NAME CHANGE:	20020103

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	IES UTILITIES INC
		DATE OF NAME CHANGE:	19940107

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	IOWA ELECTRIC LIGHT & POWER CO
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>EFFECT
<SEQUENCE>1
<FILENAME>primary_doc.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<edgarSubmission>

    <schemaVersion>X0101</schemaVersion>

    <submissionType>EFFECT</submissionType>

    <act>33</act>

    <testOrLive>LIVE</testOrLive>

    <effectiveData>
        <finalEffectivenessDispDate>2010-11-24</finalEffectivenessDispDate>
        <finalEffectivenessDispTime>10:00:00</finalEffectivenessDispTime>
        <form>S-3</form>
        <filer>
            <cik>0000052485</cik>
            <entityName>INTERSTATE POWER &amp; LIGHT CO</entityName>
            <fileNumber>333-170631</fileNumber>
        </filer>
    </effectiveData>
</edgarSubmission>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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