Amendment No. 1, dated as of April 29, 2020, to $550 million Fourth Amended and Restated Revolving Credit Agreement dated as of June 5, 2018 among CMS Energy, the Banks, as defined therein, and Barclays, as Agent

THIS AMENDMENT NO. 1 (this “Amendment”) is made as of April 29, 2020 by and among CMS Energy Corporation, a Michigan corporation (the “Company”), the financial institutions listed on the signature pages hereof and Barclays Bank PLC as administrative agent (the “Agent”), under that certain Fourth Amended and Restated Revolving Credit Agreement dated as of June 5, 2018 by and among the Company, the financial institutions from time to time party thereto (the “Banks”) and the Agent (as amended, restated, supplemented or otherwise modified from time to time, the “Credit Agreement”). Capitalized terms used herein and not otherwise defined herein shall have the respective meanings given to them in the Credit Agreement.

WHEREAS, the Company has requested that the Banks and the Agent agree to certain amendments to the Credit Agreement;

WHEREAS, the Company, the Banks and the Agent have so agreed on the terms and conditions set forth herein;

NOW, THEREFORE, in consideration of the premises set forth above, the terms and conditions contained herein, and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Company, the Banks party hereto and the Agent hereby agree to enter into this Amendment.

1.Amendments to the Credit Agreement. Effective as of April 29, 2020 (the “Amendment No. 1 Effective Date”) but subject to the satisfaction of the conditions precedent set forth in Section 2 below, the parties hereto agree that the Credit Agreement is hereby amended as follows:

(a)Section 1.1 of the Credit Agreement is hereby amended to (i) delete the definition of “Total Consolidated EBITDA” therefrom and (ii) add or amend and restate, as applicable, the following definitions in their appropriate alphabetical order therein:

“ “Affected Financial Institution” means (a) any EEA Financial Institution or (b) any UK Financial Institution.”

“ “Bail-In Action” means the exercise of any Write-Down and Conversion Powers by the applicable Resolution Authority in respect of any liability of an Affected Financial Institution.”

“ “Bail-In Legislation” means, (a) with respect to any EEA Member Country implementing Article 55 of Directive 2014/59/EU of the European Parliament and of the Council of the European Union, the implementing law, regulation, rule or requirement for such EEA Member Country from time to time which is described in the EU Bail-In Legislation Schedule and (b) with respect to the United Kingdom, Part I of the United Kingdom Banking Act 2009 (as amended from time to time) and any other law, regulation or rule applicable in the United Kingdom relating to the resolution of unsound

or failing banks, investment firms or other financial institutions or their affiliates (other than through liquidation, administration or other insolvency proceedings).”

“ “Material Subsidiary” means any Subsidiary of the Company that, on a consolidated basis with any of its Subsidiaries as of any date of determination, accounts for more than 10% of the consolidated assets of the Company and its Consolidated Subsidiaries; provided, that Enerbank USA shall not be deemed to be a Material Subsidiary at any time.”

“ “Resolution Authority” means an EEA Resolution Authority or, with respect to any UK Financial Institution, a UK Resolution Authority.”

“ “Total Consolidated Capitalization” means, at any date of determination, without duplication, the sum of (a) Total Consolidated Debt plus all amounts excluded from Total Consolidated Debt pursuant to clauses (ii), (iii) and (vii) of the proviso to the definition of such term (but only, in the case of securities of the type described in clause (iii) of such proviso, to the extent such securities have been deemed to be equity pursuant to Accounting Standards Codification Subtopic 480-10 (previously referred to as Statement of Financial Accounting Standards No. 150)), (b) equity of the common stockholders of the Company, (c) equity of the preference stockholders of the Company and (d) equity of the preferred stockholders of the Company, in each case determined at such date.”

“ “UK Financial Institution” means any BRRD Undertaking (as such term is defined under the PRA Rulebook (as amended form time to time) promulgated by the United Kingdom Prudential Regulation Authority) or any person falling within IFPRU 11.6 of the FCA Handbook (as amended from time to time) promulgated by the United Kingdom Financial Conduct Authority, which includes certain credit institutions and investment firms, and certain affiliates of such credit institutions or investment firms.”

“ “UK Resolution Authority” means the Bank of England or any other public administrative authority having responsibility for the resolution of any UK Financial Institution.”

“ “Write-Down and Conversion Powers” means, (a) with respect to any EEA Resolution Authority, the write-down and conversion powers of such EEA Resolution Authority from time to time under the Bail-In Legislation for the applicable EEA Member Country, which write-down and conversion powers are described in the EU Bail-In Legislation Schedule and (b) with respect to the United Kingdom, any powers of the applicable Resolution Authority under the Bail-In Legislation to cancel, reduce, modify or change the form of a liability of any UK Financial Institution or any contract or instrument under which that liability arises, to convert all or part of that liability into shares, securities or obligations of that person or any other person, to provide that any such contract or instrument is to have effect as if a right had been exercised under it or to suspend any obligation in respect of that liability or any of the powers under that Bail-In Legislation that are related to or ancillary to any of those powers.”

So long as any of the Obligations shall remain unpaid, any Facility LC shall remain outstanding or any Bank shall have any Commitment under this Agreement, the Company shall at all times maintain a ratio of Total Consolidated Debt to Total Consolidated Capitalization of not greater than 0.70 to 1.0.”

“12.19 Acknowledgement and Consent to Bail-In of Affected Financial Institutions. Notwithstanding anything to the contrary in any Credit Document or in any other agreement, arrangement or understanding among any such parties, each party hereto acknowledges that any liability of any Affected Financial Institution arising under any Credit Document may be subject to the Write-Down and Conversion Powers of the applicable Resolution Authority and agrees and consents to, and acknowledges and agrees to be bound by:

(a)the application of any Write-Down and Conversion Powers by the applicable Resolution Authority to any such liabilities arising hereunder which may be payable to it by any party hereto that is an Affected Financial Institution; and

(b)the effects of any Bail-In Action on any such liability, including, if applicable:

(ii)a conversion of all, or a portion of, such liability into shares or other instruments of ownership in such Affected Financial Institution, its parent entity, or a bridge institution that may be issued to it or otherwise conferred on it, and that such shares or other instruments of ownership will be accepted by it in lieu of any rights with respect to any such liability under this Agreement or any other Credit Document; or

(iii)the variation of the terms of such liability in connection with the exercise of the Write-Down and Conversion Powers of the applicable Resolution Authority.”

2.Conditions of Effectiveness. The effectiveness of this Amendment on the Amendment No. 1 Effective Date is subject to the conditions precedent that (i) the Agent shall have received counterparts of this Amendment duly executed by the Company, the Majority Banks and the Agent and (ii) the Agent shall have received payment and/or reimbursement of the Agent’s and its affiliates’ fees and expenses (including, to the extent invoiced, fees and expenses of counsel for the Agent) in connection with this Amendment.

3.Representations and Warranties of the Company. The Company hereby represents and warrants as follows:

(a)This Amendment and the Credit Agreement as modified hereby constitute legal, valid and binding obligations of the Company and are enforceable against the Company in accordance with their terms, subject to (i) the effect of applicable bankruptcy, insolvency, reorganization, moratorium or other similar laws affecting the enforcement of creditors’ rights generally and (ii) the application of general principles of equity (regardless of whether considered in a proceeding in equity or at law).

(b)As of the date hereof and after giving effect to the terms of this Amendment, (i) no Default or Event of Default has occurred and is continuing and (ii) the representations and warranties contained in Article V of the Credit Agreement, as amended hereby (and, solely with respect to the representation

contained in Section 5.6 of the Credit Agreement, after giving effect to any reports filed with the SEC prior to the date hereof), are true and correct.

(b)Upon the effectiveness hereof, each reference to the Credit Agreement in the Credit Agreement or any other Credit Document shall mean and be a reference to the Credit Agreement as amended hereby.

(c)Each Credit Document and all other documents, instruments and agreements executed and/or delivered in connection therewith shall remain in full force and effect and are hereby ratified and confirmed.

(d)Except with respect to the subject matter hereof, the execution, delivery and effectiveness of this Amendment shall not operate as a waiver of any right, power or remedy of the Agent or the Banks, nor constitute a waiver of any provision of the Credit Agreement, the Credit Documents or any other documents, instruments and agreements executed and/or delivered in connection therewith.

5.Governing Law. THIS AMENDMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH, THE INTERNAL LAW (INCLUDING SECTION 5-1401 OF THE GENERAL OBLIGATIONS LAW OF NEW YORK, BUT OTHERWISE WITHOUT REGARD TO THE LAW OF CONFLICTS) OF THE STATE OF NEW YORK, BUT GIVING EFFECT TO FEDERAL LAWS APPLICABLE TO NATIONAL BANKS.

6.Headings. Section headings in this Amendment are included herein for convenience of reference only and shall not constitute a part of this Amendment for any other purpose.

7.Counterparts. This Amendment may be executed by one or more of the parties hereto on any number of separate counterparts, and all of said counterparts taken together shall be deemed to constitute one and the same instrument. Delivery of an executed counterpart of a signature page of this Amendment by telecopy, e-mailed .pdf or any other electronic means that reproduces an image of the actual executed signature page shall be effective as delivery of a manually executed counterpart of this Amendment. The words “execution,” “signed,” “signature,” “delivery,” and words of like import in or relating to any document to be signed in connection with this Amendment and the transactions contemplated hereby shall be deemed to include Electronic Signatures, deliveries or the keeping of records in electronic form, each of which shall be of the same legal effect, validity or enforceability as a manually executed signature, physical delivery thereof or the use of a paper-based recordkeeping system, as the case may be, to the extent and as provided for in any applicable law, including the Federal Electronic Signatures in Global and National Commerce Act, the New York State Electronic Signatures and Records Act, or any other similar state laws based on the Uniform Electronic Transactions Act.

I, _______________, __________________ of CMS Energy Corporation, a Michigan corporation (the “Company”), DO HEREBY CERTIFY in connection with the Fourth Amended and Restated Revolving Credit Agreement, dated as of June 5, 2018 (as amended, restated, supplemented or otherwise modified from time to time, the “Credit Agreement”; the terms defined therein being used herein as so defined), among the Company, various financial institutions and Barclays Bank PLC, as Agent and an LC Issuer, that:

The following calculations are made in accordance with the definitions of Total Consolidated Debt and Total Consolidated Capitalization in the Credit Agreement and are correct and accurate as of __________, _____:

² For the avoidance of doubt, all reported figures shall be consistent with those reported on the Company’s most recently filed annual report on Form 10-K (or any successor form) (or, subject to the satisfaction of the requirements set forth in Section 6.7(c), any amendment thereto).