CSB Bancorp, Inc.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the Securities

Exchange Act of 1934 (Amendment No. )

Filed by the Registrant☒

Filed by a Party other than the Registrant☐

Check the appropriate box:

☐ Preliminary Proxy Statement

☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

☒ Definitive Proxy Statement

☐ Definitive Additional Materials

☐ Soliciting Material Pursuant to §240.14a-12

CSB Bancorp, Inc.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check all boxes that apply):

☒ No fee required

☐ Fee paid previously with preliminary materials

☐ Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11

2026 Proxy Statement &Notice of Annual Meeting

91 North Clay Street Millersburg, Ohio 44654

March 16, 2026

Dear Fellow Shareholders:

The 2026 Annual Meeting of Shareholders (the “Annual Meeting”) of CSB Bancorp, Inc. (“CSB”) will be held on Wednesday, April 22, 2026, at 7:00 P.M. EDT at the Carlisle Inn, located at 4949 Walnut Street, Walnut Creek, Ohio 44687.

The Meeting is being conducted for the following purposes:

To elect the following directors for terms of three years each:

To ratify the appointment of S.R. Snodgrass, P.C. as the independent registered public accounting firm for CSB for the fiscal year ending December 31, 2026;

To transact any other business that may properly come before the Annual Meeting or any adjournments thereof.

At the conclusion of the Annual Meeting, we will review highlights from the past year, The Commercial and Savings Bank’s 147 th year of existence doing business chartered by the State of Ohio. Several of the performance highlights and matters upon which we will report are outlined on page 3 of this proxy statement.

Whether or not you plan to attend the Annual Meeting, it is important that your shares be represented. Please vote your shares promptly by telephone or online, or by completing, executing, and returning the enclosed proxy card by mail in the envelope provided. To vote by phone or online, please refer to the instructions on the enclosed proxy card.

Thank you for your support of CSB.

Sincerely,

Table of Contents