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))

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).

MGE Energy, Inc. ☐ Madison Gas and Electric 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.

MGE Energy, Inc. ☐ Madison Gas and Electric Company ☐

Securities registered pursuant to Section 12(b) of the Act:

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Item 1.01. Entry into a Material Definitive Agreement.

On January 30, 2023, Madison Gas and Electric Company (MGE) amended its existing Second Amended and Restated Credit Agreement dated as of November 8, 2022 (Existing JPM Credit Agreement), with the lenders named therein and JPMorgan Chase Bank, N.A., as Administrative Agent (Administrative Agent), to increase the aggregate commitment thereunder from $60 million to $90 million.

See Item 2.03 below for further information.

Item 2.03. Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant.

On January 30, 2023, MGE entered into a First Amendment to Second Amended and Restated Credit Agreement with the lenders named therein and the Administrative Agent, which increased the aggregate commitments under the Existing JPM Credit Agreement by $30 million to $90 million. The increase reflects the exercise of an option provided in the Existing JPM Credit Agreement. No other changes were made to the Existing JPM Credit Agreement. The increase brings the total aggregate availability under MGE’s existing credit agreements to $130 million.

Forward-Looking Statements

Except for the historical information contained herein, certain of the matters discussed in this report are forward-looking statements, within the meaning of the Private Securities Litigation Reform Act of 1995, which are subject to risks and uncertainties. The factors that could cause actual results to differ materially from the forward-looking statements made by MGE Energy, Inc. (MGEE) and MGE include those factors discussed herein, as well as the items discussed in MGEE's and MGE's 2021 Annual Report on Form 10-K—ITEM 1A. Risk Factors, and other factors discussed in filings made by MGEE and MGE with the Securities and Exchange Commission. Readers are cautioned not to place undue reliance on these forward-looking statements, which apply only as of the date of this report. Neither MGEE nor MGE undertakes any obligation to publicly release any revision to its forward-looking statements to reflect events or circumstances after the date of this report, except as required by law.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits.

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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.

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