SI FINANCIAL GROUP,INC. ORGANIZED UNDER THE LAWS OF THE UNITED STATES

Exhibit 4.1

SI FINANCIAL GROUP, INC.

ORGANIZED UNDER THE LAWS OF THE UNITED STATES

FULLY PAID AND NONASSESSABLE SHARES OF COMMON STOCK $0.01 PAR VALUE

PER SHARE OF SI FINANCIAL GROUP, INC.

a stock company organized under the laws of the United States.

The shares represented by this certificate are transferable only on the stock transfer books of SI Financial Group, Inc. (the “Company”) by the holder of record hereof, or by his duly authorized attorney or legal representative, upon the surrender of this certificate properly endorsed. This certificate and the shares represented hereby are issued and shall be held subject to all the provisions of the Charter of the and any amendments thereto (copies of which are on file with the Secretary of the Company), to all of which provisions the holder by acceptance hereof, assents. The shares evidenced by this certificate are not of an insurable type and are not insured by the Federal Deposit Insurance Corporation.

IN WITNESS WHEREOF, SI Financial Group, Inc. has caused this certificate to be executed by the facsimile signatures of its duly authorized officers and has caused a facsimile of its corporate seal to be hereunto affixed.

The shares represented by this Certificate are subject to a limitation contained in the Charter to the effect that in no event shall any person, other than SI Bancorp, MHC, directly or indirectly, offer to acquire or acquire the beneficial ownership of more than 10% of the outstanding shares of common stock. Shares beneficially owned in excess of this limitation shall not be counted as shares entitled to vote and shall not be voted by any person or counted as voting shares.

The Board of Directors of the Company is authorized by resolution(s), from time to time adopted, to provide for the issuance of serial preferred stock in series and to fix and state the voting powers, designations, preferences and relative, participating, optional, or other special rights of the shares of each such series and the qualifications, limitations and restrictions thereof. The Company will furnish to any shareholder upon request and without charge a full description of each class of stock and any series thereof.

The shares represented by this Certificate may not be cumulatively voted on any matter.

The following abbreviations, when used in the inscription on the face of this certificate, shall be construed as though they were written out in full according to applicable laws or regulations:

Additional abbreviations may also be used though not in the above list.

For value received ______________ hereby sell, assign and transfer unto

PLEASE INSERT SOCIAL SECURITY OR OTHER IDENTIFICATION NUMBER OF ASSIGNEE

___________________________________________________________________________________________________________

Please print or typewrite name and address including postal zip code of assignee.

_________________________________________________________shares of the common stock represented by this certificate and do hereby irrevocably constitute and appoint

____________________________________________________________________________________, attorney, to transfer the said stock on the books of the within-named bank with full power of substitution in the premises.