THIS CERTIFIES THAT is the owner of CUSIP DATED COUNTERSIGNED AND REGISTERED: COMPUTERSHARE TRUST COMPANY, N.A. TRANSFER AGENT AND REGISTRAR, FULLY-PAID AND NON-ASSESSABLE SHARES OF THE COMMON STOCK ($.01 PAR VALUE PER SHARE) OF First Business Financial Services, Inc., transferable in person or by duly authorized attorney, upon surrender of this Certificate properly endorsed. This Certificate and the Common Stock represented hereby are subject to all of the provisions of the Articles of Incorporation and By-Laws of the Corporation and all amendments thereto. IN WITNESS WHEREOF the Corporation has caused this Certificate to be signed by its duly authorized officers (by facsimile signatures). COMMON STOCK PAR VALUE $.01 COMMON STOCK THIS CERTIFICATE IS TRANSFERABLE IN CANTON, MA AND NEW YORK, NY SEE REVERSE FOR CERTAIN DEFINITIONS Certificate Number Shares . FIRST BUSINESS FINANCIAL SERVICES, INC. INCORPORATED UNDER THE LAWS OF THE STATE OF WISCONSIN President and Chief Executive Officer Sr. Vice President & Corporate Secretary By AUTHORIZED SIGNATURE 016570| 003590|127C|RESTRICTED||4|057-423 319390 10 0 <<Month Day, Year>> * * 600620* * * * * * * * * 600620* * * * * * * * * 600620* * * * * * * * * 600620* * * * * * * * * 600620* * ** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Sample **** Mr. Sample **600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares*** *600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares**** 600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****6 00620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****60 0620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600 620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares***600620**Shares****600620**Shares****60062 0**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620 **Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620* *Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620** Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**S hares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Shares****600620**Sh * * * SIX HUNDRED THOUSAND SIX HUNDRED AND TWENTY* * * MR. SAMPLE & MRS. SAMPLE & MR. SAMPLE & MRS. SAMPLE NNNNN ZQ 000000 Certificate Numbers 1234567890/1234567890 1234567890/1234567890 1234567890/1234567890 1234567890/1234567890 1234567890/1234567890 1234567890/1234567890 Total Transaction Num/No. 123456 Denom. 123456 Total 1234567 MR A SAMPLE DESIGNATION (IF ANY) ADD 1 ADD 2 ADD 3 ADD 4 PO BOX 43004, Providence, RI 02940-3004 CUSIP XXXXXX XX X Holder ID XXXXXXXXXX Insurance Value 1,000,000.00 Number of Shares 123456 DTC 12345678 123456789012345

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: TEN COM - as tenants in common UNIF GIFT MIN ACT - Custodian TEN ENT - as tenants by the entireties under Uniform Gifts to Minors Act JT TEN - as joint tenants with right of survivorship UNIF TRF MIN ACT Custodian (until age). and not as tenants in common (Cust) (Minor) under Uniform Transfers to Minors Act (State) Additional abbreviations may also be used though not in the above list. For value received, hereby sell, assign and transfer unto Shares Attorney Dated: 20 Signature: Signature: Notice: The signature to this assignment must correspond with the name as written upon the face of the certificate, in every particular, without alteration or enlargement, or any change whatever. (Cust) (Minor) (State) PLEASE INSERT SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER OF ASSIGNEE (PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING POSTAL ZIP CODE, OF ASSIGNEE) of the common stock represented by the within Certificate, and do hereby irrevocably constitute and appoint to transfer the said stock on the books of the within-named Corporation with full power of substitution in the premises. . FIRST BUSINESS FINANCIAL SERVICES Signature(s) Guaranteed: Medallion Guarantee Stamp THE SIGNATURE(S) SHOULD BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (Banks, Stockbrokers, Savings and Loan Associations and Credit Unions) WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM, PURSUANT TO S.E.C. RULE 17Ad-15.