CORRESP

Interstate Power and Light Company
Alliant Energy Tower
200 First Street SE
Cedar Rapids, Iowa 52401

August 4, 2008

Securities and Exchange Commission
100 F Street, N.E.
Washington, D.C. 20549

Re: Interstate Power and Light Company. –
Registration Statement on Form S-3, as amended (Registration No. 333-151898)

Ladies and Gentlemen:

        Pursuant to Rule 461 under the Securities Act of 1933, as amended, the undersigned Registrant hereby requests that the above-referenced Registration Statement be declared effective at 10:00 a.m. Eastern Time on August 6, 2008, or as soon as is practicable thereafter.

        In connection with requesting acceleration of the effective date of the Registration Statement, the undersigned Registrant hereby acknowledges the following:

    •       should the Securities and Exchange Commission (the “Commission”) or its staff (the “Staff”), acting pursuant to delegated authority, declare the Registration Statement effective, it does not foreclose the Commission from taking any action with respect to the Registration Statement;

    •       the action of the Commission or the Staff, acting pursuant to delegated authority, in declaring the Registration Statement effective, does not relieve the Registrant from its full responsibility for the adequacy and accuracy of the disclosure in the Registration Statement; and

    •       the Registrant may not assert Staff comments and the declaration of effectiveness as a defense in any proceeding initiated by the Commission or any person under the federal securities laws of the United States.

Very truly yours,

INTERSTATE POWER AND LIGHT COMPANY

By:  /s/ William D. Harvey

        Name: William D. Harvey

        Title: Chairman and Chief Executive Officer

COVER

		FOLEY & LARDNER LLP ATTORNEYS AT LAW
		777 EAST WISCONSIN AVENUE MILWAUKEE, WISCONSIN 53202-5306 414.271.2400  TEL 414.297.4900  FAX www.foley.com
	August 4, 2008	WRITER’S DIRECT LINE 414.297.5817 jlochmann@foley.com  EMAIL
VIA EDGAR AND FACSIMILE		CLIENT/MATTER NUMBER 026162-0121

Securities and Exchange Commission
100 F Street, N.E.
Washington, D.C. 20549

Attention: Blair Petrillo

Re: Interstate Power and Light Company –
Registration Statement on Form S-3, as amended (Registration No. 333-151898)

Ladies and Gentlemen:

        On behalf of Interstate Power and Light Company, an Iowa corporation (the “Company”), we are enclosing the Company’s acceleration request relating to the above-referenced Registration Statement pursuant to Rule 461 under the Securities Act. As indicated in the acceleration request, it is respectfully requested that the above-referenced Registration Statement be declared effective at 10:00 a.m., Eastern Time, on August 6, 2008, or as soon as is practicable thereafter.

        Should any questions arise in connection with this filing, please contact the undersigned at (414) 297-5817 or John K. Wilson at (414) 297-5642.

Very truly yours,

/s/ Jessica S. Allen

Jessica S. Allen

cc: Interstate Power and Light Company
  Patricia L. Kampling
  Enrique Bacalao
  Jake Blavat
Foley & Lardner
  Benjamin F. Garmer, III
  Jay O. Rothman
  John K. Wilson

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