Company: ASB
Filing Date: 2025-12-04
Form Type: 425
Source: 0001193125-25-307510
Chunk: 5

Company: ASSOCIATED BANC-CORP
Filing Date: 2025-12-04
Form: 425
Chunk 5
---
 the Associated board of directors, and Associated agreed to register such shares of Associated Common Stock on the terms and subject to the conditions set forth in the Shareholders’ Agreement. The transfer restrictions
prohibit transfers of Associated Common Stock in the first sixty days following the completion of the merger and, for the remainder of the period through the first anniversary, among other things, limits the public sale of shares to 150,000 shares
per day (unless pursuant to a broadly distributed underwritten offering). The transfer and voting obligations will terminate at such time when the former American National voting shareholders cease to hold at least 5% of outstanding Associated
voting securities, and each such shareholder’s registration rights will terminate once such shareholder no longer holds any registrable securities of Associated.

The foregoing description of the Shareholders’ Agreement does not purport to be complete and is qualified in its entirety by reference
to the full text of the Shareholders’ Agreement, which is attached hereto as Exhibit 10.1 and incorporated herein by reference.

Item 3.02 Unregistered Sales of Equity Securities.

The information set forth under Item 1.01 of this Report on Form 8-K with respect to the issuance of Associated Common Stock to the American National voting shareholders is incorporated herein by reference. The issuance of the Associated Common Stock to American National voting
shareholders in the Merger is expected to be exempt from the registration requirements of the Securities Act of 1933, as amended (the “Securities Act”), under Section 4(a)(2) of the Securities Act.

4

Item 9.01 Financial Statements and Exhibits. (d) Exhibits

| Exhibit 
 No.     
 2.1     
 10.1    |     | Description of Exhibit                                                                                                                            
 Agreement and Plan of Merger, dated as of November 30, 2025, by and between Associated Banc-Corp and American National Corporation                
 Transfer, Voting and Registration Rights Agreement, dated as of November 30, 2025, between Associated Banc-Corp and the other signatories thereto |
|:--------|:----|:--------------------------------------------------------------------------------------------------------------------------------------------------|
| 104     |     | The cover page from this Current Report on Form 8-K, formatted in Inline XBRL                                                                     |

5

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This communication may contain certain forward-looking statements, including, but not limited to, certain plans, expectations, goals, projections, and
statements about the benefits of the proposed transaction,