<PAGE>
FILED PURSUANT TO RULE 424(B)(1)
REGISTRATION NO. 333-27427
SUPPLEMENT DATED
JUNE 4, 1997 TO
PROSPECTUS
$400,000,000
WASHINGTON MUTUAL CAPITAL I
SKISSM
8 3/8% SUBORDINATED CAPITAL INCOME SECURITIES
(LIQUIDATION AMOUNT $1,000 PER CAPITAL SECURITY)
FULLY AND UNCONDITIONALLY GUARANTEED TO THE EXTENT SET FORTH HEREIN BY
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The 8 3/8% Subordinated Capital Income Securities (the "Capital Securities")
offered hereby represent undivided beneficial ownership interests in the assets
of Washington Mutual Capital I, a Delaware statutory business trust (the
"Trust"). Washington Mutual, Inc., a Washington corporation ("Washington Mutual"
or the "Company"), will be the owner of all of the beneficial ownership
interests represented by common securities of the Trust (the "Common
Securities"; together with the Capital Securities, the "Trust Securities"). The
Trust exists for the sole purpose of issuing the Capital Securities and the
Common Securities and investing the proceeds thereof in 8 3/8% Junior
Subordinated Debentures (the "Junior Subordinated Debentures") to be issued by
the Company.
(CONTINUED ON NEXT PAGE)
SEE "RISK FACTORS" BEGINNING ON PAGE 14 HEREOF FOR CERTAIN INFORMATION
RELEVANT TO AN INVESTMENT IN THE CAPITAL SECURITIES.
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THESE SECURITIES HAVE NOT BEEN APPROVED OR DISAPPROVED BY THE SECURITIES AND
EXCHANGE COMMISSION OR ANY STATE SECURITIES COMMISSION NOR HAS THE
SECURITIES AND EXCHANGE COMMISSION OR ANY STATE SECURITIES
COMMISSION PASSED UPON THE ACCURACY OR ADEQUACY OF THIS
PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY
IS A CRIMINAL OFFENSE.
THESE SECURITIES ARE NOT DEPOSITS OR OTHER OBLIGATIONS OF A BANK OR SAVINGS
ASSOCIATION AND ARE NOT INSURED OR GUARANTEED BY THE FEDERAL DEPOSIT
INSURANCE CORPORATION OR ANY OTHER GOVERNMENTAL AGENCY.
<TABLE>
<CAPTION>
Initial Public Underwriting Proceeds to
Offering Price (1) Commissions (2) Trust (3)(4)
<S> <C> <C> <C>
Per Capital Security..................................... $998.16 (3) $998.16
Total.................................................... $399,264,000 (3) $399,264,000
</TABLE>
(1) Plus accrued distributions, if any, from June 4, 1997.
(2) The Trust and the Company have each agreed to indemnify the several
Underwriters against certain liabilities, including liabilities under the
Securities Act of 1933, as amended (the "Securities Act"). See
"Underwriting."
(3) In view of the fact that the proceeds of the sale of the Capital Securities
will be invested in the Junior Subordinated Debentures, the Company has
agreed to pay to the Underwriters, as compensation for their arranging the
investment therein of such proceeds, $10 per Capital Security (or $4,000,000
in the aggregate). See "Underwriting."
(4) Before deducting expenses payable by the Company, estimated at $235,304.
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The Capital Securities are offered, subject to prior sale, when, as and if
issued to and accepted by the several Underwriters and subject to certain
conditions. It is expected that delivery of the Capital Securities will be made
in book-entry form through the facilities of The Depository Trust Company on or
about June 4, 1997 at the offices of Lehman Brothers Inc., New York, New York
against payment therefor in immediately available funds.
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LEHMAN BROTHERS
CHASE SECURITIES INC.
SALOMON BROTHERS INC
UBS SECURITIES
May 30, 1997
