Form 8-K 07-27-2004

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

_________________

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of
the Securities Exchange Act of 1934

_________________

  Date of Report  
  (Date of earliest  
  event reported): July 27, 2004

  Alliant Energy Corporation  
(Exact name of registrant as specified in its charter)

Wisconsin 1-9894 39-1380265
(State or other (Commission File (IRS Employer
jurisdiction of Number) Identification No.)
incorporation)

4902 North Biltmore Lane, Madison, Wisconsin 53718
(Address of principal executive offices, including zip code)

(608) 458-3311
(Registrant's telephone number)

Item 5.   Other Events and Regulation FD Disclosure.

  The information in Item 12, excluding the "2004 Earnings Guidance" section from the Alliant Energy Corporation press release, is incorporated by reference herein.

Item 7.   Financial Statements and Exhibits.

  (a)   Not applicable.

  (b)   Not applicable.

  (c)   Exhibits. The following exhibits are being furnished herewith:

    (99.1)   Alliant Energy Corporation press release dated July 27, 2004.

Item 12.   Results of Operations and Financial Condition.

        On July 27, 2004, Alliant Energy Corporation issued a press release announcing its earnings for the second quarter ended June 30, 2004 and its earnings guidance for 2004. A copy of such press release is furnished as Exhibit 99.1 and is incorporated by reference herein. Alliant Energy is including non-GAAP (non-accounting principles generally accepted in the United States of America) financial information to enable investors to better understand the core businesses of Alliant Energy.

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SIGNATURES

        Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

  ALLIANT ENERGY CORPORATION
   
   
Date: July 27, 2004 By: /s/ John E. Kratchmer
          John E. Kratchmer
          Vice President-Controller and Chief
          Accounting Officer

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ALLIANT ENERGY CORPORATION

Exhibit Index to Current Report on Form 8-K
Dated July 27, 2004

Exhibit
Number

(99.1)     Alliant Energy Corporation press release dated July 27, 2004.

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