Reg FD Disclosure

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) August 18, 2020 Name of Registrant, State of Incorporation, Address of Principal Executive Offices, Telephone Number, Commission File Number, IRS Employer Identification Number ALLIANT ENERGY CORP ORATION (a Wisconsin Corporation) 4902 N. Biltmore Lane Madison , Wisconsin 53718 Telephone ( 608 ) 458-3311 Commission File Number - 1-9894 IRS Employer Identification Number - 39-1380265   (Former name or former address, if changed since last report.) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions: ☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act: Alliant Energy Corporation, Common Stock, $0.01 Par Value , Trading Symbol LNT , Nasdaq Global Select Market Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ Item 7.01 Regulation FD Disclosure. On August 18, 2020, Alliant Energy Corporation posted investor materials which included a discussion of earnings guidance to its investor relations website. A copy of such investor materials related to earnings guidance is furnished as Exhibit 99.1. Item 9.01 Financial Statements and Exhibits. (a) Not applicable. (b) Not applicable. (c) Not applicable. (d) Exhibits . The following exhibit is being furnished herewith: Exhibit Number Description (99.1) Alliant Energy Investor Materials related to earnings guidance (104) Cover Page Interactive Data File (embedded within the Inline XBRL document) 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: August 18, 2020 By: /s/ Robert J. Durian   Robert J. Durian   Executive Vice President and Chief Financial Officer