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                                                                     Exhibit 5.1

                                  LAW OFFICES
                      ELIAS, MATZ, TIERNAN & HERRICK L.L.P.
                                  12TH FLOOR
                             734 15TH STREET, N.W.
                            WASHINGTON, D.C. 20005

                                   ----------

                            TELEPHONE: (202) 347-0300
                            FACSIMILE: (202) 347-2172
                                  WWW.EMTH.COM


                                 August 1, 2001


Board of Directors
PFS Bancorp, Inc.
Second and Bridgeway Streets
Aurora, Indiana  47001

Gentlemen:

         We have acted as special counsel to PFS Bancorp, Inc. (the "Company")
in connection with the preparation and filing with the Securities and Exchange
Commission pursuant to the Securities Act of 1933, as amended, of the
Registration Statement on Form SB-2 (the "Registration Statement"), relating to
the issuance of up to 1,551,293 shares of the Company's common stock, par value
$.01 per share (the "Common Stock"), in connection with the conversion of
Peoples Federal Savings Bank, Aurora, Indiana (the "Bank") from mutual to stock
form and the reorganization of the Bank as a subsidiary of the Company (the
"Conversion").

         In this regard, we have examined the Articles of Incorporation and
Bylaws of the Company, resolutions of the Board of Directors of the Company and
the Bank, the Plan of Conversion of the Bank ("Plan of Conversion"), and such
other documents and matters of law as we deemed appropriate for the purposes of
this opinion. This opinion is limited to federal laws and regulations and the
laws of the State of Indiana which are in effect on the date hereof.

         Based upon the foregoing, we are of the opinion as of the date hereof
that the Common Stock has been duly and validly authorized, and when issued in
accordance with the terms of the Plan of Conversion, and upon the receipt of the
consideration required thereby, will be legally issued, fully paid and
non-assessable.

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Board of Directors
PFS Bancorp, Inc.
August 1, 2001
Page 2
         We hereby consent to the filing of this opinion as an exhibit to the
Company's Registration Statement and to the references to this firm under the
headings "The Conversion - Tax Aspects" and "Legal and Tax Opinions" in the
Prospectus contained in the Registration Statement.


                                    Very truly yours,

                                    ELIAS, MATZ, TIERNAN & HERRICK L.L.P.



                                    By: /s/ KEVIN M. HOULIHAN
                                        ----------------------------------------
                                        Kevin M. Houlihan, a Partner