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): September 30, 2026

MARATHON BANCORP, INC.

(Exact Name of Registrant as Specified in its Charter)


Maryland	001-42608	86-2191258
(State or Other Jurisdiction)	(Commission File No.)	(I.R.S. Employer
of Incorporation)		Identification No.)

500 Scott Street, Wausau, Wisconsin		54402
(Address of Principal Executive Offices)		(Zip Code)

Registrant’s telephone number, including area code: (715) 845-7331

Not Applicable

(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 (see General Instruction A.2. below):

☐

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))

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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, $0.01 par value		MBBC		The Nasdaq Stock Market LLC

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 5.02

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On September 30, 2026, Joy C. Selting-Buchberger, the Chief Financial Officer of Marathon Bancorp, Inc. (the “Company”) and Marathon Bank (the “Bank”) informed the Boards of Directors of the Company and the Bank of her decision to retire as Chief Financial Officer of the Company and the Bank on July 2, 2027.

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.

		Marathon Bancorp, Inc.
DATE: October 1, 2026	By:	/s/ Nicholas W. Zillges
		Nicholas W. Zillges President and Chief Executive Officer