Winchester Bancorp (WSBK) S-1 IPO registration

Exhibit 99.5

STOCK ORDER FORM SEND OVERNIGHT PACKAGES TO: Winchester Savings Bank Attn: Stock Information Center 661 Main St. Winchester, MA 01890 [phone number] Deadline: The Subscription Offering ends at 12:00 p.m., Eastern Time, on [Expiration Date]. Your original Stock Order Form, properly executed and with the correct payment, must be received (not postmarked) by the deadline or it will be considered void. Orders may be delivered to the address on the top of this form or by hand delivery to the Stock Information Center. Faxes or copies of this form may not be accepted. Winchester Bancorp, Inc. reserves the right to accept or reject improperly completed stock order forms. (1) Number of Shares (2) Total Amount Due Price Per Share $ X $10.00 = THE MINIMUM PURCHASE IS 25 SHARES ($250). No person may purchase more than 25,000 shares ($250,000). Also, no person together with an associate or group of persons acting in concert may purchase more than 75,000 shares ($750,000). (3a) Method of Payment – Cash, Check or Money Order Enclosed is cash, a personal check, bank check or money order $ made payable to Winchester Bancorp, Inc. in the amount of: Checks will be cashed upon receipt. (3b) Method of Payment – Certificate or Savings Account Withdrawal ONLY The undersigned authorizes withdrawal from the Winchester Savings Bank deposit account(s) listed below. There will be no early withdrawal penalty applicable for withdrawals authorized on this form. Funds designated for withdrawal must be in the account(s) listed at the time this form is received. Winchester Savings Bank IRAs or accounts with check-writing privileges may NOT be listed for direct withdrawal below. Winchester Savings Bank Deposit Account Number(s) Withdrawal Amount(s) $ $ $ Total Withdrawal Amount $ (4) Purchaser Priority Check the one box that applies to the purchaser(s) listed in Section 8: a. Eligible Account Holders – Check here if you were a depositor with aggregate account balances of $50 with Winchester Savings Bank as of the close of business on November 30, 2023. Enter information in Section 9 for all deposit accounts that you had at Winchester Savings Bank on this date. b. Employees, Officers, Directors, Trustees and Corporators – Check here if you are not an Eligible Account Holder but are an employee, officer, director, trustee or corporator of Winchester Savings Bank. c. Local Community – Check here if you are not included in 4(a) or 4(b), and you reside in the Massachusetts cities and towns of Arlington, Beverly, Danvers, Lexington, Lynn, Malden, Medford, Melrose, Peabody, Reading, Salem, Saugus, Stoneham, Wakefield, Winchester or Woburn. d. General Public – Check here if none of the above priorities apply to you. (5) Check if you (or a household family member or relative) are a Winchester Savings Bank, Winchester Bancorp, Inc. or Winchester Bancorp, MHC: Employee Officer Director Trustee Corporator (6) Maximum Purchaser Identification: Check here if you, individually or together with others (see section 7), are subscribing for the maximum purchase allowed and are interested in purchasing more shares if the maximum purchase limitation is increased. See Item 1 of the Stock Order Form Instructions. (7) Associates/Acting in Concert: Check here if you, or any associates or persons acting in concert with you (defined on reverse side), have submitted other orders for shares. If you check this box, list below all other orders submitted by you or your associates or by persons acting in concert with you. Name(s) listed in Section 8 on other Order Forms Shares Ordered Name(s) listed in Section 8 on other Order Forms Shares Ordered (8) Stock Registration: (to appear on stock registration statement) Please PRINT legibly and fill out completely Form of Ownership (check one box and fill in SS# or Tax ID #): IRA / Qualified Plan Order IRA or other qualified plan Individual Tenants in Common Uniform Transfers to SS or Tax ID Minors Act (minor SS#) Reporting _________________________ TTEE Tax ID# _________– Joint Tenants Corporation / Partnership Trust – Under Agreement SS or Tax ID Dated ____________________ Other _________________________ Owner SS# _________–__________Name Name Address Daytime Telephone # City State Zip Code County Evening Telephone # (9) Qualifying Accounts: You should list any accounts that you have or had with Winchester Savings Bank in the box below. SEE THE STOCK ORDER FORM INSTRUCTIONS FOR FURTHER DETAILS. All subscription orders are subject to the provisions of the stock offering as described in the prospectus. Attach a separate page if additional space is needed. Failure to list all of your accounts may result in the loss of part or all of your subscription rights if the offering is oversubscribed. NAMES ON ACCOUNTS ACCOUNT NUMBERS (10) Acknowledgement, Certification and Signature: I understand that to be effective, this form, properly completed, together with full payment or withdrawal authorization, must be received by Winchester Bancorp, Inc. (not postmarked) no later than 12:00 p.m., Eastern Time, on [Expiration Date] otherwise this form and all of my subscription rights will be void. (continued on reverse) *** ORDER NOT VALID UNLESS SIGNED *** ONE SIGNATURE REQUIRED, UNLESS SECTION (3b) OF THIS FORM INCLUDES ACCOUNTS REQUIRING MORE THAN ONE SIGNATURE TO AUTHORIZE WITHDRAWAL Signature Date Signature Date Internal Use Only: 914289 Date Rec’d-_____ 002 /_____ -Part Check# -4 _____________ $_________________ 10Dec24 Check# 16:45 _____________ $__________________ Page Batch# 109 __________ Order # ________Priority_______

(7) Associates/Acting in Concert (continued from front side of Stock Order Form)

Associate – The term “associate” of a person means:

1) any corporation or organization, other than Winchester Savings Bank, Winchester Bancorp, Inc., Winchester Bancorp, MHC or a majority-owned subsidiary of these entities, of which the person is a senior officer, partner or 10% or greater beneficial stockholder;

2) any trust or other estate in which the person has a substantial beneficial interest or serves as a trustee or in a fiduciary capacity; excluding any employee stock benefit plan in which the person has a substantial beneficial interest or serves as trustee or in a fiduciary capacity; and

3) any blood or marriage relative of the person, who either resides with the person or who is a director, trustee, corporator or officer of Winchester Savings Bank, Winchester Bancorp, Inc. or Winchester Bancorp, MHC

Acting in Concert – The term “acting in concert” means:

1) Persons seeking to combine or pool their voting or other interests in the securities of an issuer for a common purpose, pursuant to any contract, understanding, relationship, agreement or other arrangement, whether written or otherwise. When persons act together for such purpose, their group is deemed to have acquired their stock. The determination of whether a group is acting in concert shall be made solely by us and may be based on any evidence upon which we choose to rely.

Please see the Prospectus section entitled “The Reorganization and Offering – Additional Limitations on Common Stock Purchases” for more information on purchase limitations and a more detailed description of “associates” and “acting in concert.”

(10) Acknowledgement, Certification and Signature (continued from front side of Stock Order Form)

I agree that after receipt by Winchester Bancorp, Inc., this Stock Order Form may not be modified or cancelled without Winchester Bancorp, Inc.’s consent, and that if withdrawal from a deposit account has been authorized, the authorized amount will not otherwise be available for withdrawal. Under penalty of perjury, I certify that (1) the Social Security or Tax ID information and all other information provided hereon are true, correct and complete, (2) I am purchasing shares solely for my own account and that there is no agreement or understanding regarding the sale of such shares, or my right to subscribe for shares, and (3) I am not subject to backup withholding tax [cross out (3) if you have been notified by the IRS that you are subject to backup withholding.] I acknowledge that my order does not conflict with the maximum purchase limitation of $250,000 for any individual or $750,000 with associates of, or persons acting in concert with, such person, or entity, in all categories of the offering, combined as set forth in the Plan of Reorganization from a Mutual Savings Bank to a Mutual Holding Company and Plan of Stock Issuance and the Prospectus.

Subscription rights pertain to those eligible to subscribe in the Subscription Offering. Federal and state regulations prohibit any person from transferring or entering into any agreement directly or indirectly to transfer the legal or beneficial ownership of subscription rights, or the underlying securities, to the account of another.

I ACKNOWLEDGE THAT THE SHARES OF COMMON STOCK ARE NOT DEPOSITS OR SAVINGS ACCOUNTS AND ARE NOT INSURED BY THE FEDERAL DEPOSIT INSURANCE CORPORATION, THE DEPOSITOR INSUTANCE FUND OR ANY OTHER GOVERNMENT AGENCY.

I further certify that, before purchasing the common stock of Winchester Bancorp, Inc., I received the Prospectus. While not required, we encourage you to read the Prospectus, including disclosure concerning the nature of the security being offered and the risks involved in the investment described in the “Risk Factors” section, which risks include but are not limited to the following:

[RISK FACTORS TO BE INSERTED FROM FINAL PROSPECTUS]

EXECUTION OF THIS CERTIFICATION FORM WILL NOT CONSTITUTE A WAIVER OF ANY RIGHTS THAT A PURCHASER MAY HAVE UNDER THE SECURITIES ACT OF 1933 AND THE SECURITIES EXCHANGE ACT OF 1934, BOTH AS AMENDED.

Winchester Bancorp, Inc.

Stock Order Form Instructions

Stock Order Form Instructions – All orders are subject to the provisions of the stock offering as described in the Prospectus.

Item 1 and 2 – Number of Shares and Total Amount Due – Fill in the number of shares that you wish to purchase and the total payment due. The amount due is determined by multiplying the number of shares ordered by the subscription price of $10.00 per share. The minimum number of shares of common stock you may order is 25 shares ($250). The maximum number of shares that can be ordered by any person in the offering, or persons exercising subscription rights through a single qualifying account held jointly, is 25,000 shares ($250,000), and no person together with an associate or group of persons acting in concert may purchase more than 75,000 shares ($750,000) in all categories in the offering combined. Please see the Prospectus section entitled “The Reorganization and Offering – Additional Limitations on Common Stock Purchases” for more specific information.

Item 3a – Payment by Check – Payment for shares may be made by cash (in person delivery only), personal check, bank check or money order payable to Winchester Bancorp, Inc. DO NOT MAIL CASH. Funds received during the offering will be held in a segregated account at Winchester Savings Bank and will earn interest at a rate of 0.10% per annum until completion or termination of the offering.

Item 3b – Payment by Account Withdrawal – To pay by withdrawal from a savings account or certificate of deposit at Winchester Savings Bank, insert the account number(s) and the amounts(s) you wish to withdraw from each account. If more than one signature is required for a withdrawal, all signatories must sign in the signature box on the front of the Stock Order Form. To withdraw from an account with check writing privileges, please write a check. Winchester Savings Bank will waive any applicable penalties for early withdrawal from certificate of deposit accounts (CDs) for the purpose of purchasing stock in the offering. A hold will be placed on the account(s) for the amount(s) you indicate to be withdrawn. Payments will remain in account(s) until the offering closes and will earn their respective rate of interest, but will not be available for your use until the completion of the transaction.

Item 4 – Purchaser Priority – Check the appropriate box that applies to you and any others subscribing for shares with this order form. If boxes (a) and (b) do not apply to you, then check the Local Community or General Public box, as appropriate.

Item 5 – Management/Employee/Family – Please check one of the boxes if you are an employee, officer (VP and above), director, trustee or corporator of Winchester Savings Bank, Winchester Bancorp, Inc. or Winchester Bancorp, MHC or a member or relative of such person’s household.

Item 6 – Maximum Purchase – Please check the box, if applicable. If you check the box but have not subscribed for the maximum amount and did not complete Item 7, you may not be eligible to purchase more shares in the event maximum purchase limitations are increased.

Item 7 – Associates/Acting in Concert – Check the box, if applicable, and provide the requested information. Attach a separate page, if necessary. In the Prospectus dated [date], please see the section entitled “The Reorganization and Offering – Additional Limitations on Common Stock Purchases” for more information regarding the definition of “associate” and “acting in concert.”

Item 8 – Stock Registration – The stock transfer industry has developed a uniform system of shareholder registrations that we will use in the issuance of Winchester Bancorp, Inc. common stock. See the reverse side of this form for further details regarding common forms of stock registration. Please complete this section as fully and accurately as possible, and be certain to supply your social security or Tax I.D. number(s) and your daytime and evening phone numbers. We will need to call you if we cannot execute your order as given. If you have any questions regarding the registration of stock, please consult your legal advisor or contact the Stock Information Center at [phone number]. Subscription rights are not transferable. If you are an eligible account holder or other member, as defined in the Prospectus, to protect your priority rights over other purchasers as described in the Prospectus, you cannot add the names of others for joint stock registration unless they are also named on the qualifying deposit account (with certain exceptions for IRA and Keogh purchases).

Item 9 – Qualifying Accounts – List all qualifying accounts that you had with Winchester Savings Bank if you checked off box (a) in Item 4. For example, if you are ordering stock in just your name, you should list all of your account numbers that you were a qualifying customer of Winchester Savings Bank. Similarly, if you are ordering stock jointly with another customer, you should list all account numbers under which either of you are owners, i.e., individual accounts, joint accounts, etc. If you are ordering stock in your minor child’s or grandchild’s name under the Uniform Transfers to Minors Act, the minor must have had an account number as of November 30, 2023 and you should list only their account number(s). If you are ordering stock as a corporation, partnership or other legal business entity, you need to list just that entity’s account number(s), as your individual account number(s) do not qualify. Failure to list all of your qualifying account numbers may result in the loss of part or all of your subscription rights if the offering is oversubscribed.

Item 10 – Acknowledgement, Certification & Signature – Sign and date the form where indicated. Before you sign please carefully review the information you have provided and read the acknowledgement and both sides of the Stock Order Form. Only one signature is required, unless any account listed in section 3b of this form requires more than one signature to authorize a withdrawal. Please review the Prospectus before making an investment decision.

If you have any questions regarding the offering, please call our Stock Information Center at [phone number] to speak to a representative of Raymond James & Associates, Inc. Representatives are available by telephone Monday – Friday, 10:00 a.m. – 4:00 p.m., Eastern Time. You may want to meet in person with a representative by visiting our Stock Information Center located at our office at 661 Main Street, Winchester, MA. The Stock Information Center will be closed on weekends and bank holidays.

(See Reverse Side for Stock Ownership Guide)

Winchester Bancorp, Inc.

Stock Order Form Instructions

Stock Ownership Guide

Individual – The stock is to be registered in one individual’s name only. Provide only this individual’s information.

Joint Tenants – Joint tenants with rights of survivorship identifies two or more owners. When stock is held by joint tenants with rights of survivorship, ownership automatically passes to the surviving joint tenant(s) upon the death of any joint tenant. All parties must agree to the transfer or sale of shares held by joint tenants.

Tenants in Common – Tenants in common may also identify two or more owners. When stock is held by tenants in common, upon the death of one co-tenant, ownership of the stock will be held by the surviving co-tenant(s) and by the heirs of the deceased co-tenant. All parties must agree to the transfer or sale of shares held by tenants in common.

Corporation/Partnership – Corporations, partnerships or other legal business entities may purchase stock. Please provide the corporation or partnership’s legal name and Tax I.D. To have subscription rights within a customer priority, the corporation or partnership must have an account in its legal name and Tax I.D. Please contact the Stock Information Center to verify customer rights and purchase limitations.

Uniform Transfers to Minors Act (“UTMA”) – For residents of Massachusetts and many states, stock may be held in the name of a custodian for the benefit of a minor under the Uniform Transfers to Minors Act. In this form of ownership, the minor is the actual owner of the stock with the adult custodian being responsible for the investment until the child reaches legal age. Only one custodian and one minor may be designated.

Registration for UTMA:	On Name Line 1: print the name of the custodian followed by the abbreviation “CUST”
	On Name Line 2: FBO (for benefit of) followed by the name of the minor, followed by UTMA-MA
	(or your state’s abbreviation)
	List only the minor’s social security number on the form.

Fiduciary/Trust – Generally, fiduciary relationships (such as trusts, estates, guardianships, etc.) are established under a form of trust agreement or pursuant to a court order. Without a legal document establishing a fiduciary relationship, your stock may not be registered in a fiduciary capacity. To have subscription rights within a customer priority, the fiduciary or trust must have an account in its legal name and Tax I.D. Please contact the Stock Information Center to verify customer rights and purchase limitations.

Instructions: On the first name line, print the first name, middle initial, and last name of the fiduciary if the fiduciary is an individual. If the fiduciary is a corporation, list the corporate title on the first name line. Following the name, print the fiduciary title, such as trustee, executor, personal representative, etc. On the second name line, print the name of the maker, donor or testator or the name of the beneficiary. Following the name, indicate the type of legal document establishing the fiduciary relationship (agreement, court order, etc.) In the blank after “Under Agreement Dated” form of ownership box, fill in the date of the document governing the relationship. The date of the document need not be provided for a trust created by a will.

Individual Retirement Accounts – Individual Retirement Account (“IRA”) holders may potentially make stock purchases from their existing IRA if it is a self-directed IRA, or through a prearranged “trustee-to-trustee” transfer if their IRA is currently at Winchester Savings Bank. The stock cannot be held in a Winchester Savings Bank account. Please contact your broker or self-directed IRA provider as quickly as possible to explore this option, as it may take a number of weeks to complete a trustee-to-trustee transfer and place a subscription in this manner.

IRA registration:	On Name Line 1 – list the name of the broker or trust department followed by CUST or TRUSTEE.
	On Name Line 2 – FBO (for benefit of) YOUR NAME [IRA a/c #________].
	Address will be that of the broker/trust department to where the ownership statement will be sent.
	List the Social Security/Tax I.D. numbers of the trustee’s and IRA/Qualified Plan Order owner in the lines as indicated.
	Please list your phone numbers, not the phone numbers of your broker / trust department.

If you have any questions regarding the offering, please call our Stock Information Center at [phone number] to speak to a representative of Raymond James & Associates, Inc. Representatives are available by telephone Monday – Friday, 10:00 a.m. – 4:00 p.m., Eastern Time. You may want to meet in person with a representative by visiting our Stock Information Center located at our office at 661 Main Street, Winchester, MA. The Stock Information Center will be closed on weekends and bank holidays.

(See Reverse Side for Stock Order Form Instructions)