Exhibit 4.1



                     WASHINGTON MUTUAL FINANCE CORPORATION,

                                    CITICORP,

                                  AS GUARANTOR,

                                       AND

                      WACHOVIA BANK, NATIONAL ASSOCIATION,

                                   AS TRUSTEE




                             Supplemental Indenture

                           Dated as of January 9, 2004



                                  to Indenture

                           Dated as of October 1, 1997



<PAGE>



            THIS SUPPLEMENTAL INDENTURE dated as of January 9, 2004 (the
"Supplemental Indenture"), by and among Washington Mutual Finance Corporation
(formerly known as Aristar, Inc.), a corporation organized and existing under
the laws of the State of Delaware ("Washington Mutual"), Citicorp, a corporation
organized and existing under the laws of the State of Delaware, as guarantor,
and Wachovia Bank, National Association (as successor to First Union National
Bank), a national banking association, as trustee (the "Trustee");

            WHEREAS, Washington Mutual has heretofore executed and delivered to
the Trustee an indenture dated as of October 1, 1997 (the "Indenture"),
providing for the issuance by Washington Mutual from time to time of its senior
debt securities;

            WHEREAS, on the date hereof, Washington Mutual will become a wholly
owned subsidiary of Citicorp;

            WHEREAS, Citicorp desires to fully and unconditionally guarantee the
payment obligations of Washington Mutual with respect to Washington Mutual's
issued and outstanding senior securities under the Indenture (the "Notes") as
set forth herein; and

            WHEREAS, the execution of the Supplemental Indenture is authorized
and permitted by Section 901(10) of the Indenture and all conditions precedent
provided for in the Indenture relating to the execution of the Supplemental
Indenture have been complied with;

            NOW, THEREFORE, THIS SUPPLEMENTAL INDENTURE WITNESSETH: That in
order to effectuate the guarantee described herein, Citicorp agrees with the
Trustee, for the equal and proportionate benefit of the respective Holders from
time to time of the Notes (the "Holders"), as follows:

                                    ARTICLE I
                                    Guarantee

            Citicorp does hereby fully and unconditionally guarantee (the
"Guarantee") to the Holders the due and punctual payment of the principal of and
interest on all the Notes, according to their tenor (the "Obligations"), in
accordance with the provisions of the Indenture, as supplemented, as provided
below:

                       (a) Notice of acceptance of the Guarantee and of default
of performance by Washington Mutual is expressly waived, and payment under the
Guarantee shall be subject to no condition other than the giving of a written
request for payment in accordance with the provisions of the Indenture, stating
the fact of default of performance, mailed to Citicorp at the following address:
Citicorp, Office of Corporate Treasury, 153 East 53rd Street, 6th Floor, New
York, New York 10043, Attention: Treasurer.


<PAGE>


                       (b) The right of the Holders under any debt instrument of
Washington Mutual that is outstanding as of the date hereof to claim payment
from Citicorp under the Citicorp Guarantee shall rank in priority of payment
with Citicorp's other obligations to exactly the same extent that the
Obligations of Washington Mutual under such debt instrument rank with Washington
Mutual's other obligations if any.

                       (c) The obligations of Citicorp under the Guarantee shall
in no way be impaired by: (1) any extension, amendment, modification or renewal
of the Obligations; (2) any waiver of any event of default, extension of time or
failure to enforce any of the Obligations; or (3) any extension, moratorium or
other relief granted to Washington Mutual pursuant to any applicable law or
statute.

                       (d) The Guarantee shall be irrevocably valid until, and
no claim may be asserted under the Guarantee after, the earliest to occur of:
(1) the tenth business day following the maturity date of all the Notes, either
upon their respective stated maturities, redemption or otherwise; and (2) the
date on which Washington Mutual ceases to be a wholly owned subsidiary of
Citicorp, as set forth in an Officer's Certificate of Citicorp delivered to the
Trustee.

                       (e) Citicorp shall be obligated to make payment under the
Guarantee only by payment to the Trustee, for the benefit of the Holders, at the
same address as Washington Mutual is obligated to make payment, provided that
such address must be in the United States.

                       (f) Citicorp shall have no obligation to make payment or
take action under the Guarantee during any period when payment by Washington
Mutual, in accordance with the provisions of the Indenture, would constitute a
violation of any applicable laws (other than bankruptcy, liquidation,
reorganization or similar laws affecting the enforcement of the rights of
creditors generally).

                       (g) Citicorp may, upon providing written notice of such
assignment to the Trustee, assign its obligations under the Guarantee to an
affiliate; provided that such affiliate shall have, at the date of such
assignment, (1) a rating on its long-term, unsecured and unsubordinated
indebtedness for borrowed money from any of Fitch Ratings (or any successor
thereto, "Fitch"), Moody's Investors Service (or any successor thereto,
"Moody's") or Standard & Poor's Rating Services (or any successor thereto,
"Standard & Poor's") that is no lower than the rating then assigned by any of
Fitch, Moody's or Standard & Poor's to the long-term, unsecured and
unsubordinated indebtedness of Citicorp, or (2) assets and liabilities such
that, if its long-term, unsecured and unsubordinated indebtedness for borrowed
money were rated by any of Fitch, Moody's or Standard & Poor's, such rating
would be either (A) higher or (B) no lower than two rating modifiers below the
rating then assigned by any of Fitch, Moody's or Standard & Poor's to the
long-term, unsecured and unsubordinated indebtedness of Citicorp. In the event
of an assignment, such assignee shall be substituted in lieu of Citicorp with
respect to the performance of the Obligations theretofore to be performed


<PAGE>


by Citicorp as described in this Article One, provided that, if such assignee
ceases to be an affiliate of Citicorp at any time prior to the termination of
the Guarantee, the Guarantee shall be deemed to be re-assigned to Citicorp,
which shall be deemed to be substituted in lieu of such assignee with respect to
the performance of the Obligations to be performed by such assignee. No consent
of any holder of Notes is required to effect such assignment or re-assignment.
For purposes of this subsection (g), the term "affiliate" shall mean any
corporation incorporated under the laws of the United States which is either a
direct or indirect wholly-owned subsidiary of Citigroup Inc.

                                   ARTICLE II
                            Miscellaneous Provisions

            SECTION II.1 Reports by Washington Mutual. Information, documents or
reports required to be filed with the Trustee by Washington Mutual pursuant to
Section 704 of the Indenture shall be deemed filed with the Trustee if (a) such
information, documents or reports are generally available on, and can be printed
and/or downloaded from, the Securities and Exchange Commission's internet
website, www.sec.gov (or any other website of which Washington Mutual notifies
the Trustee), and (b) the Trustee has been notified by Washington Mutual that
such information, documents or reports have been filed with the Securities and
Exchange Commission.

            SECTION II.2 Execution as Supplemental Indenture. This Supplemental
Indenture is executed and shall be construed as an indenture supplemental to the
Indenture and, as provided in the Indenture, this Supplemental Indenture forms a
part thereof. Except as herein expressly otherwise defined, the use of the terms
and expressions herein is in accordance with the definitions, uses and
constructions contained in the Indenture. Except as expressly amended hereby,
the Indenture shall continue in full force and effect in accordance with the
provisions thereof and the Indenture is in all respects hereby ratified and
confirmed.

            SECTION II.3 Responsibility for Recitals, etc. The recitals herein
and in the Notes (except in the Trustee's certificate of authentication) shall
be taken as the statements of Washington Mutual, and the Trustee assumes no
responsibility for the correctness thereof. The Trustee makes no representations
as to the validity or sufficiency of this Supplemental Indenture or of the
Notes. The Trustee makes no undertakings or representations in respect of, and
shall not be responsible in any manner whatsoever for and in respect of, the
validity or sufficiency of this Supplemental Indenture or the proper
authorization or the due execution hereof by Washington Mutual or for or in
respect of the recitals and statements contained herein, all of which recitals
and statements are made solely by Washington Mutual.

            SECTION II.4 Provisions Binding on Successors. All of the covenants,
stipulations, premises and agreements made in this Supplemental Indenture by
Washington Mutual and Citicorp shall bind their respective successors and
assigns whether so expressed or not.


<PAGE>


            SECTION II.5 New York Contract. This Supplemental Indenture shall be
deemed to be a contract made under the laws of the State of New York and for all
purposes shall be construed in accordance with the laws of said State.

            SECTION II.6 Execution and Counterparts. This Supplemental Indenture
may be executed in any number of counterparts, each of which when so executed
shall be deemed to be an original, but all such counterparts shall together
constitute but one and the same instrument.


<PAGE>


            IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed, and their respective corporate seals to be
hereunto affixed and attested, all as of the day and year first above written.

                                  WASHINGTON MUTUAL FINANCE CORPORATION

                                  By: /s/ James R. Garner
                                     -------------------------------------------
                                     Name:  James R. Garner
                                     Title:  Executive Vice President


                                  CITICORP, as Guarantor

                                  By: /s/ Martin A. Waters
                                     -------------------------------------------
                                     Name:  Martin A. Waters
                                     Title:  Vice President


                                  WACHOVIA BANK, NATIONAL ASSOCIATION,
                                  as Trustee

                                  By: /s/ John C. Stephens III
                                     -------------------------------------------
                                     Name:  John C. Stephens III
                                     Title:  Vice President


<PAGE>


STATE OF Utah      )
                   )  ss.:
COUNTY OF Summit   )

         On this 9th day of January, 2004 before me personally
came James R. Garner, to me personally known, who, being by me duly
sworn, did depose and say that he/she is a/an/the Executive Vice President of
Washington Mutual Finance Corporation, one of the corporations described in and
which executed the above instrument, that he/she knows the corporate seal of
said corporation, that the seal affixed to said instrument is such corporate
seal, that it was so affixed by authority of the Board of Directors of said
corporation, and that he/she signed his/her name thereto by like authority.


[NOTARIAL SEAL]

                                      /s/ Susan Irwin
                                     -------------------------------------------
                                                    Notary Public


<PAGE>


STATE OF New York  )
                   ) ss.:
COUNTY OF Queens   )

         On this 9th day of January, 2004 before me personally came
Martin A. Waters, to me personally known, who, being by me duly sworn, did
depose and say that he/she is a/an/the Vice President of Citicorp, one of
the corporations described in and which executed the above instrument, that
he/she knows the corporate seal of said corporation, that the seal affixed to
said instrument is such corporate seal, that it was so affixed by authority of
the Board of Directors of said corporation, and that he/she signed his/her name
thereto by like authority.


[NOTARIAL SEAL]

                                      /s/ Victoria J. Pusateri
                                     -------------------------------------------
                                                    Notary Public


<PAGE>



STATE OF           )
                   )  ss.:
COUNTY OF          )

         On this 9th day of January, 2004 before me personally came
John C. Stephens III, to me personally known, who, being by me duly sworn, did
depose and say that he/she is a/an/the Vice President of Wachovia Bank,
National Association, one of the corporations described in and which executed
the above instrument, that he/she knows the corporate seal of said corporation,
that the seal affixed to said instrument is such corporate seal, that it was so
affixed by authority of the Board of Directors of said corporation, and that
he/she signed his/her name thereto by like authority.


[NOTARIAL SEAL]

                                      /s/ Stephanie A. Moore
                                     -------------------------------------------
                                                    Notary Public