Avidia Bancorp, Inc.

S-11 d923214ds1.htm S-1

As filed with the Securities and Exchange Commission on March 14, 2025

**Registration No. 333-________ **

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

**FORMS-1 **

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

Avidia Bank 401(k) Plan

(Exact Name of Registrant as Specified in Its Charter)

42 Main Street

Hudson, Massachusetts 01749

**(800)508-2265 **

(Address, Including Zip Code, and Telephone Number, Including Area Code, of Registrant’s Principal Executive Offices)

Robert D. Cozzone

President and Chief Executive Officer

42 Main Street

Hudson, Massachusetts 01749

**(800)508-2265 **

(Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent for Service)

Copies to:

Lawrence M.F. Spaccasi, Esq.

Kent M. Krudys, Esq.

Victor L. Cangelosi, Esq.

Luse Gorman, PC

5335 Wisconsin Avenue, N.W., Suite 780

Washington, D.C. 20015

**(202)274-2028 **

**Approximate date of commencement of proposed sale to the public:**As soon as practicable after this registration statement becomes effective.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933 check the following box: ☒

If this Form is filed to register additional shares for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering: ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering: ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering: ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, anon-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act:

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 7(a)(2)(B) of the Securities Act: ☐

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

Prospectus Supplement

Interests in

401(k) PLAN AS ADOPTED BY AVIDIA BANK

Offering of Participation Interests of up to 4,920,964 Shares of

Avidia Bancorp, Inc. Common Stock

In connection with themutual-to-stock conversion of Assabet Valley Bancorp, Avidia Bancorp, Inc. (“Avidia Bancorp”), a newly formed Maryland corporation and the proposed holding company of Avidia Bank, is offering shares of its common stock for sale at $10.00 per share. Following the completion of the conversion and stock offering, it is expected that the common stock of Avidia Bancorp will be listed on the New York Stock Exchange under the symbol “AVBC”. The conversion and stock offering is not contingent on receipt of approval to list on the New York Stock Exchange.

In connection with the conversion and stock offering, Avidia Bank is allowing participants in the 401(k) Plan, as adopted by Avidia Bank (the “401(k) Plan”), to invest a portion of their account balances in Avidia Bancorp common stock. This prospectus supplement relates to elections by 401(k) Plan participants to direct the trustee of the 401(k) Plan to invest up to 50% of their account balances in the 401(k) Plan in Avidia Bancorp common stock in connection with the conversion and stock offering. Based upon the value of the 401(k) Plan assets at December 31, 2024, the trustee of the 401(k) Plan could purchase up to 4,920,964 shares of Avidia Bancorp common stock on behalf of participants, at the purchase price of $10.00 per share.

Before you consider investing, you should read the prospectus of Avidia Bancorp, dated _______, 2025, which is enclosed with this prospectus supplement. It contains detailed information regarding the conversion, the stock offering of Avidia Bancorp, and the financial condition, results of operations and business of Assabet Valley Bancorp and Avidia Bank. This prospectus supplement provides information regarding the 401(k) Plan. You should read this prospectus supplement together with the prospectus and keep both for future reference.

For a discussion of risks that you should consider, see “Risk Factors” beginning on page of the attached prospectus, and “Notice of Your Rights Concerning Employer Securities” in this prospectus supplement.

The interests in the 401(k) Plan and the offering of shares of Avidia Bancorp common stock have not been approved or disapproved by the Securities and Exchange Commission, the Board of Governors of the Federal Reserve System, the Massachusetts Division of Banks, the Federal Deposit Insurance Corporation or any state securities regulator. Any representation to the contrary is a criminal offense.

The securities offered by this prospectus supplement are not deposits or savings accounts and are not insured or guaranteed by the Federal Deposit Insurance Corporation, the Massachusetts Depositors Insurance Fund or any other governmental agency.

This prospectus supplement may be used only in connection with offers and sales by Avidia Bancorp in the stock offering of Avidia Bancorp common stock that may be acquired within the 401(k) Plan. No one may use this prospectus supplement to reoffer or resell interests in shares of Avidia Bancorp common stock acquired through the 401(k) Plan.

You should rely only on the information contained in this prospectus supplement and the attached prospectus. Avidia Bancorp, Assabet Valley Bancorp, Avidia Bank and the 401(k) Plan have not authorized anyone to provide you with different information.

This prospectus supplement does not constitute an offer to sell or solicitation of an offer to buy any securities in any jurisdiction to any person to whom it is unlawful to make an offer or solicitation in that jurisdiction. Neither the delivery of this prospectus supplement and the attached prospectus nor any sale of Avidia Bancorp common stock shall under any circumstances imply that there has not been a change in the affairs of Avidia Bancorp, Assabet Valley Bancorp, Avidia Bank or the 401(k) Plan since the date of this prospectus supplement, or that the information contained in this prospectus supplement or incorporated by reference is correct as of any time after the date of this prospectus supplement.

The date of this prospectus supplement is _______, 2025.

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