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                                 EXHIBIT 5.1


                                March 16, 1995

Board of Directors
Washington Mutual, Inc.
1201 Third Avenue
Seattle, Washington 98101

Ladies and Gentlemen:

        We have acted as counsel for Washington Mutual, Inc., a Washington
Corporation (the "Company") in connection with the proposed merger (the
"Merger) of Olympus Capital Corporation ("Olympus") with and into the Company
in accordance with the terms of that certain Amended and Restated Agreement for
Merger dated as of January 20, 1995 among the Company, Washington Mutual Bank,
Washington Mutual Federal Savings Bank, Olympus and Olympus Bank, a Federal
Savings Bank (the "Merger Agreement") and the preparation and filing of a
Registration Statement ("Registration Statement") on Form S-4 under the
Securities Act of 1933, as amended for up to 3,002,621 shares (the "Shares") of
the Company's common stock, no par value per share, that are issuable to
shareholders of Olympus as consideration for the surrender of their shares of
Olympus Common Stock in the Merger. We have examined the Registration
Statement, the Merger Agreement and such other documents and records as we deem
necessary for the purpose of this opinion.

        Based on the foregoing, we are of the opinion that upon the issuance of
the Shares in accordance with the terms of the Merger Agreement and the
Registration Statement, the Shares will be legally issued, fully paid and
nonassessable.

        We hereby consent to the filing of this Opinion as an Exhibit to the
Registration Statement and to the reference to our firm in the Prospectus
included in the Registration Statement under the caption entitled "Legal
Matters."


                                         Very truly yours,

                                         FOSTER PEPPER & SHEFELMAN


                                         /s/  ROBERT C. SEIDEL
                                         ----------------------------
                                              Robert C. Seidel


