Form 8-K

8-K — ASSOCIATED BANC-CORP

Accession: 0001104659-26-109643

Filed: 2026-09-22

Period: 2026-09-21

CIK: 0000007789

SIC: 6022 (STATE COMMERCIAL BANKS)

Item: Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Item: Financial Statements and Exhibits

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 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 21, 2026

Associated Banc-Corp

(Exact name of registrant as specified in its charter)

Wisconsin

001-31343

39-1098068

(State or other jurisdiction of incorporation)

(Commission

File Number)

(IRS Employer Identification No.)

433 Main Street, Green Bay, Wisconsin

54301

(Address of principal executive offices)

(Zip code)

Registrant’s telephone number, including area code

(920) 491-7500

(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))

¨ 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, par value $0.01 per share

ASB

The New York Stock Exchange

Depositary Shrs, each representing 1/40th intrst in a shr of 5.875% Non-Cum. Perp Pref Stock, Srs E

ASB PrE

The New York Stock Exchange

Depositary Shrs, each representing 1/40th intrst in a shr of 5.625%

Non-Cum. Perp Pref Stock, Srs F ASB PrF The New York Stock Exchange

6.625%

Fixed-Rate Reset Subordinated Notes due 2033 ASBA The New York Stock Exchange

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.

As previously announced, Randall J. Erickson, Executive Vice President,

General Counsel and Corporate Secretary of Associated Banc-Corp (the “Company”), will retire from his position, effective

October 13, 2026 (“Effective Date”). Mr. Erickson will remain in an advisory capacity through the end of 2026 to ensure a

successful transition of his duties. In connection with the transition, the Company and Mr. Erickson entered into the Employment Transition

– Letter Agreement dated September 21, 2026 (the “Letter Agreement”), providing that Mr. Erickson will serve in the

role of Attorney-Advisor from the Effective Date to January 4, 2027 (the “Retirement Date”), reporting to the Company’s

Chief Executive Officer and having such duties, authority and responsibility as the Chief Executive Officer and the General Counsel and

Corporate Secretary shall determine. In addition, the Letter Agreement sets forth, without limitation, the following material terms:

· Mr. Erickson will maintain his current base salary through the Retirement Date.

· He will also retain all vested rights in the Company’s 401(k) plan, Supplemental Executive Retirement Plan, and Retirement Account

Plan and will receive all payments due to him under the terms of those plans.

· He is eligible to participate in the Company’s short-term incentive program through the Retirement Date, and he will receive

the full amount of his 2026 short-term incentive as calculated in accordance with applicable metrics.

· He will continue to vest in any unvested awards under the 2025-2027 Long-Term Incentive Performance Plan (“LTIPP”) and

2026-2028 LTIPP, all of which are issued under and governed by the 2025 Equity Incentive Plan and the award agreements issued thereunder.

The foregoing description of the material terms of the Letter Agreement

is a summary only and is qualified in its entirety by reference to the text of the Letter Agreement, a copy of which is attached hereto

as Exhibit 10.1 and is incorporated herein by reference.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits

10.1

Letter Agreement, dated September 21, 2026

104

Cover Page Interactive Data File the cover page XBRL tags are embedded within the Inline XBRL document

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.

Associated Banc-Corp

(Registrant)

Date: September 21, 2026

By:

/s/ Randall J. Erickson

Randall J. Erickson

Executive Vice President, General Counsel and Corporate Secretary

EX-10.1 — EXHIBIT 10.1

EX-10.1

Filename: tm2625936d1_ex10-1.htm · Sequence: 2

Exhibit 10.1

Associated Banc-Corp

September 21, 2026

VIA EMAIL ONLY

Mr. Randall J. Erickson

111 East Kilbourn Avenue, Suite 200

Milwaukee, WI 53202

Randall.Erickson@associatedbank.com

Re: Employment Transition – Letter Agreement

Dear Randy:

The purpose of this letter

agreement (the “Agreement”) is to memorialize the terms of the employment transition that you will soon make from Executive

Vice President, General Counsel and Corporate Secretary, to Attorney-Advisor. If you agree to these terms, please sign and date where

indicated and return a copy to me.

As you know, you are currently

Executive Vice President, General Counsel and Corporate Secretary, and hold certain offices with Associated Banc-Corp (“ASB”)

and its subsidiaries.

As you also know, we agree

that you will transition your employment to Attorney-Advisor, upon the terms and conditions set forth herein.

NOW, THEREFORE, in consideration

of the mutual covenants and agreements set forth in this Agreement, the receipt and sufficiency of which are hereby acknowledged, the

parties agree as follows:

1.             At-Will Employment.

Subject to the terms and conditions of this Agreement, you will agree to continue employment and serve in the position described in this

Agreement. Your employment with the Company is and shall remain “at will,” which means that you may resign from your employment,

or the Company may terminate your employment, at any time, for any reason or no reason, and with or without notice, subject to the terms

hereof.

2.             Effective

Date. The parties agree that your employment hereunder and the terms and conditions of this Agreement will commence and be effective

as of October 13, 2026 (the “Effective Date”).

3.             Relinquishment

of Positions. You agree that, as of the Effective Date, and without further action, you shall: (i) cease to be a member of ASB’s

Executive Leadership Team; (ii) cease to be an “executive officer” under applicable securities laws; and (iii) no

longer be an “officer” under Regulation O under Federal Reserve regulations.

4.             Position

and Duties.

(a)             Position.

Upon the Effective Date, you shall serve as the Attorney-Advisor reporting exclusively to the Chief Executive Officer. In such position,

you shall have such duties, authority and responsibility as shall be determined by the Chief Executive Officer and the General Counsel

and Corporate Secretary.

(b)             Duties.

You shall devote substantially all of your business time and attention to the performance of your duties hereunder and will not engage

in any other business, profession or occupation for compensation or otherwise which would conflict or interfere with the performance of

such services either directly or indirectly. Notwithstanding the foregoing, you will be permitted to (i) act or serve as a director,

trustee, committee member or principal of any type of business, civic or charitable organization, and (ii) purchase or own less than

five percent (5%) of the publicly traded securities of any corporation.

Date. The parties acknowledge and affirm that you will retire from your employment with ASB, effective January 4, 2027 (the “Retirement

Date”). You shall be deemed to have resigned from all positions with ASB as of the Retirement Date without any further action

required by you or ASB to effectuate such resignation; provided, however, upon ASB’s request, you shall take all action deemed necessary

by ASB to ensure and/or document the effect of same. Notwithstanding this provision, ASB, through its Chief Executive Officer, may request

that you postpone your retirement for a reasonable amount of time, and you agree to engage in discussions with ASB regarding a change

to the Retirement Date.

5.             Compensation

and Benefits.

(a)             Base

Salary. You will maintain your current base salary from the Effective Date until the Retirement Date, payable in regular semi-monthly

installments, in accordance with the Company’s usual payroll procedures (the “Salary”).

(b)             Vested

Incentives. You will retain all your vested rights in the Company’s 401(k) plan, Supplemental Executive Retirement plan,

and Retirement Account Plan and will receive all payments due you under the terms of those plans.

of Short-Term Incentives. Notwithstanding the Effective Date of this Agreement, you shall continue to be entitled to participate in

ASB’s short-term incentive program through the Retirement Date. You will receive the full amount of your 2026 short-term incentive,

calculated in accordance with the ASB and individual performance metrics set out in applicable plans, consistent with ASB’s Incentive

Compensation General Terms & Conditions that provide for payment of such short-term incentive in the event of a retirement occurring

after the end of the applicable plan year but before the incentive payment date. ASB will take any action necessary to seek requisite

approval from the Compensation and Benefits Committee of the Board of Directors to pay the full 2026 short-term incentive. After that

date, subject to the terms of those plans and incentive compensation terms and conditions, you shall no longer be eligible for any of

the bonus or short-term incentive plans that are applicable to executives or non-executive colleagues.

(d)             Sunset

of Long-Term Incentives. Notwithstanding the Effective Date of this Agreement, you will continue to vest in any unvested awards under

the 2025-2027 Long-Term Incentive Performance Plan (“LTIPP”) and 2026-2028 LTIPP, all of which are issued under and governed

by the 2025 Equity Incentive Plan and the award agreements issued thereunder. The terms and conditions of such plan and award agreements

shall continue to apply.

(e)             Acknowledgement

of Clawback Obligation. You acknowledge and agree that you remain subject to ASB’s Clawback Policy, which may require you to

surrender certain compensation earned, subject to the terms and conditions of such policy.

(f)             Other

Compensation and Benefit Arrangements. You shall be entitled to participate in any and all benefit programs that are available to

non-Executive Leadership Team members, such as health insurance and 401(k) retirement, that are available to non-Executives, provided

that you are eligible to participate under the plan documents governing those programs.

(g)            Supplemental

Executive Retirement Plan. ASB will present the Compensation and Benefits Committee of the Board of Directors with a resolution to

approve an annual benefit accrual for 2026, in accordance with the terms of the Associated Banc-Corp Supplemental Executive Retirement

Plan.

(h)             Withholdings

and Taxes. All payments to you will be payable pursuant to ASB’s normal payroll practices. ASB shall deduct from all payments

to you hereunder any federal, state or local withholding or other taxes or charges which ASB is from time to time required to deduct under

applicable law, and all amounts payable to you hereunder are stated herein before any such deductions.

6.             Relinquishment

of Change of Control Agreement. You are party to a Change of Control Agreement with ASB (the “COC Agreement”) which

provides for certain compensation to you in the event of a change in control. In consideration for the benefits provided to you under

this Agreement, upon the Effective Date, you hereby waive and relinquish any and all rights or claims under the COC Agreement.

7.             Attorneys’

Fees. In the event that ASB brings any action to enforce any of the provisions of this Agreement, or to obtain money damages for the

breach thereof, all expenses, including reasonable attorneys’ fees, shall be paid by you if ASB is the prevailing party.

8.             Other

Agreements. You acknowledge and agree that you have certain covenants and obligations that are not outlined in this Agreement. Other

than the COC Agreement, the parties agree that the terms and conditions of any other written agreements between the parties shall remain

in full force and effect.

9.             Counterparts.

This Agreement may be executed in separate counterparts, each of which is deemed to be an original and all of which taken together constitute

one and the same agreement.

10.           Choice

of Law. All issues concerning the construction, validity, enforcement and interpretation of this Agreement shall be governed by and

construed in accordance with the laws of the State of Wisconsin, without giving effect to any choice of law or conflict of law rules or

provisions (whether of the State of Wisconsin or any other jurisdiction) that would cause the application of the laws of any jurisdiction

other than the State of Wisconsin.

11.           Amendments

and Waiver. The provisions of this Agreement may be amended or waived only by a written instrument, with written consent by both ASB

and you, and no course of conduct or failure or delay in enforcing the provisions of this Agreement shall affect the validity, binding

effect or enforceability of this Agreement.

Sincerely,

/s/ Andrew J. Harmening

Andrew J. Harmening

Chief Executive Officer

Associated Banc-Corp

ACKNOWLEDGED AND AGREED

Randall J. Erickson

/s/ Randall J. Erickson

Date:

9/21/2026

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Sep. 21, 2026

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