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) May 15, 2013

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:

Item 7.01. Regulation FD Disclosure.

On May 17, 2013, CMS Energy Corporation and Consumers Energy Company are holding their annual meetings of shareholders. A copy of the presentation to attendees at the annual meetings is furnished as Exhibit 99.1 to this report.

In accordance with General Instruction B.2 of Form 8-K, the information in this Current Report on Form 8-K, Item 7.01, including Exhibit 99.1, shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth in such a filing.

Item 8.01. Other Events.

On May 15, 2013, the Michigan Public Service Commission (“MPSC”) approved a partial settlement agreement in Consumers Energy Company’s electric rate case, increasing Consumers Energy Company’s retail electric rates by $89 million annually. The partial settlement agreement was previously described in the Form 8-K filed on May 7, 2013. The settlement agreement and the May 15, 2013 MPSC order do not cover certain specified issues relating to the Advanced Metering Infrastructure program.

The rates authorized by the May 15, 2013, MPSC order will go into effect for service rendered on and after May 16, 2013.

For more information and to obtain a copy of the order please visit the MPSC’s website at: http://efile.mpsc.state.mi.us/efile/viewcase.php?casenum=17087.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits.

This Form 8-K contains “forward-looking statements” as defined in Rule 3b-6 of the Securities Exchange Act of 1934, as amended, Rule 175 of the Securities Act of 1933, as amended, and relevant legal decisions. The forward-looking statements are subject to risks and uncertainties. They should be read in conjunction with “FORWARD-LOOKING STATEMENTS AND INFORMATION” and “RISK FACTORS” sections of CMS Energy Corporation’s Form 10-K and Consumers Energy Company’s Form 10-K each for the Year Ended December 31, 2012 and as updated in CMS Energy Corporation’s and Consumers Energy Company’s Forms 10-Q for the Quarter Ended March 31, 2013. CMS Energy Corporation’s and Consumers Energy Company’s “FORWARD-LOOKING STATEMENTS AND INFORMATION” and “RISK FACTORS” sections are incorporated herein by reference and discuss important factors that could cause CMS Energy Corporation’s and Consumers Energy Company’s results to differ materially from those anticipated in such statements.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrants have duly caused this report to be signed on their behalf by the undersigned hereunto duly authorized.

Exhibit Index

99.1 Presentation dated May 17, 2013