Form 8-K

8-K — MGE ENERGY INC

Accession: 0001193125-26-334011

Filed: 2026-08-05

Period: 2026-08-05

CIK: 0001161728

SIC: 4900 (ELECTRIC, GAS & SANITARY SERVICES)

Item: Results of Operations and Financial Condition

Item: Regulation FD Disclosure

Item: Financial Statements and Exhibits

Documents

8-K — mgee-20260805.htm (Primary)

EX-99.1 (mgee-ex99_1.htm)

EX-99.2 (mgee-ex99_2.htm)

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8-K

8-K (Primary)

Filename: mgee-20260805.htm · Sequence: 1

8-K

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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

August 5, 2026

Date of report (date of earliest event reported)

Commission

File No.

Name of Registrant, State of Incorporation, Address

of Principal Executive Offices, and Telephone No.

IRS Employer

Identification No.

000-49965

MGE Energy, Inc.

(a Wisconsin Corporation)

133 South Blair Street

Madison, Wisconsin 53788

(608) 252-7000 | mgeenergy.com

39-2040501

000-1125

Madison Gas and Electric Company

(a Wisconsin Corporation)

133 South Blair Street

Madison, Wisconsin 53788

(608) 252-7000 | mge.com

39-0444025

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:

Title of each class

Trading symbol(s)

Name of each exchange on which registered

Common Stock, $1 Par Value Per Share

MGEE

The NASDAQ Stock 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).

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 ☐

Item 2.02. Results of Operations and Financial Condition.

On August 5, 2026, MGE Energy, Inc. (the Company) issued a press release announcing its second quarter 2026 earnings. The Company is furnishing a copy of that press release as Exhibit 99.1 to this report.

This combined Form 8-K is being furnished separately by the Company and Madison Gas and Electric Company. Information contained herein relating to any individual registrant has been furnished by such registrant on its own behalf. Neither registrant makes any representation as to information relating to the other registrant.

Item 7.01. Regulation FD Disclosure.

On August 5, 2026, MGE Energy, Inc. posted a financial presentation on its Investor Relations website. A copy of the presentation is attached as Exhibit 99.2. This Form 8-K and the attached exhibits are furnished to, but not filed with, the Securities and Exchange Commission.

Item 9.01. Financial Statements and Exhibits.

(a) Financial statements of businesses acquired: None

(b) Pro forma financial information: None

(d) Exhibits.

Exhibit No.

Description

99.1

Press release of MGE Energy, Inc., issued on August 5, 2026.

99.2

Presentation Slides.

104

Cover Page Interactive Data File (the cover page XBRL tags are embedded in the Inline XBRL document).

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.

MGE Energy, Inc.

Madison Gas and Electric Company

(Registrants)

Date: August 5, 2026

/s/ Jenny L. Lagerwall

Jenny L. Lagerwall

Assistant Vice President - Accounting and Controller

(Chief Accounting Officer)

EX-99.1

Filename: mgee-ex99_1.htm · Sequence: 2

EX-99.1

EXHIBIT 99.1

News

MGE Energy Reports Second-Quarter 2026 Earnings

Madison, Wis., August 05, 2026—MGE Energy, Inc. (Nasdaq: MGEE), today reported financial results for the second quarter of 2026.

MGE Energy's GAAP (Generally Accepted Accounting Principles) earnings for the second quarter of 2026 were $33.4 million, or $0.89 per share, compared to $26.5 million, or $0.72 per share, for the same period in the prior year.

Electric segment earnings increased $3.0 million for 2026 compared to 2025, reflecting strategic capital investments that grew rate base, largely driven by the successful deployment of key renewable energy projects. Gas net income remained stable compared to the second quarter of 2025. In addition, earnings benefited from approximately $3.9 million of investment gains, including returns from venture capital funds focused on technologies and innovations relevant to the evolving energy industry.

MGE Energy, Inc.

(In thousands, except per-share amounts)

(Unaudited)

Three Months Ended June 30,

2026

2025

Operating revenues

161,195

159,452

Operating income

32,634

34,223

Net income

33,353

26,498

Earnings per share - basic

0.89

0.73

Earnings per share - diluted

0.89

0.72

Weighted average shares outstanding - basic

37,351

36,540

Weighted average shares outstanding - diluted

37,456

36,569

Six Months Ended June 30,

2026

2025

Operating revenues

403,898

378,422

Operating income

85,786

87,088

Net income

81,834

68,090

Earnings per share - basic

2.21

1.86

Earnings per share - diluted

2.21

1.86

Weighted average shares outstanding - basic

36,972

36,526

Weighted average shares outstanding - diluted

37,029

36,557

About MGE Energy

MGE Energy is a public utility holding company. Its principal subsidiary, Madison Gas and Electric, generates and distributes electricity to 170,000 customers in Dane County, Wis., and purchases and distributes natural gas to 180,000 customers in seven south-central and western Wisconsin counties. MGE's roots in the Madison area date back more than 150 years.

Forward-looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended. Such forward-looking statements are based on MGE Energy's current expectations, estimates and assumptions regarding future events, which are inherently uncertain. We caution you not to place undue reliance on any forward-looking statements, which are made as of the date of this press release. We undertake no obligation to revise or update publicly any such forward-looking statements to reflect any change in expectations or in events, conditions or circumstances on which any such statements may be based. For a further description of the risks and uncertainties that could cause actual results to differ from those expressed in these forward-looking statements, as well as risks relating to our business in general, please refer to the “Risk Factors” sections in our Annual Report on Form 10-K for the year ended December 31, 2025, filed with the Securities and Exchange Commission.

Contact:

Steve B. Schultz

Media Relations

608-252-7219 | sbschultz@mge.com

Ken Frassetto

Investor Relations

608-252-4723 | kfrassetto@mge.com

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