<PAGE>

                                                                     Exhibit 4.6

                                                                  EXECUTION COPY



                        SUPPLEMENTAL SERVICING AGREEMENT

         THIS SUPPLEMENTAL SERVICING AGREEMENT is made as of June 30, 2004 (this
"Agreement"), among American Express Travel Related Services Company, Inc., a
New York corporation (the "Servicer"), American Express Centurion Bank, a Utah
industrial loan corporation ("Centurion"), American Express Bank, FSB, a federal
savings bank ("FSB," and together with Centurion, the "Subservicers"), American
Express Receivables Financing Corporation III LLC, a Delaware limited liability
company ("RFC III"), American Express Receivables Financing Corporation IV LLC,
a Delaware limited liability company ("RFC IV"), and American Express
Receivables Financing Corporation II, a Delaware corporation ("RFC II," and
together with RFC III and RFC IV, the "Transferors").

                                    RECITALS

         WHEREAS, the Servicer and the Transferors are parties to the Pooling
and Servicing Agreement, dated as of May 16, 1996, as amended and restated as of
April 16, 2004 (as so amended and restated and as further amended and
supplemented from time to time, the "Pooling and Servicing Agreement"), among
the Transferors, the Servicer, and The Bank of New York, as Trustee (in such
capacity, the "Trustee"); and

         WHEREAS, pursuant to the Pooling and Servicing Agreement, the Servicer
has agreed to service and administer, or cause to be serviced and administered,
the Receivables; and

         WHEREAS, the Transferors and the Servicer desire to memorialize in this
Agreement the terms on which the Servicer shall be compensated for servicing and
administering the Receivables allocated to the Transferors' Interest pursuant to
the Pooling and Servicing Agreement; and

         WHEREAS, subject to the terms and conditions of this Agreement, the
Servicer desires to engage the Subservicers to subservice and administer certain
Receivables; and

         WHEREAS, each Subservicer desires to accept such engagement and the
rights, powers, duties, and obligations set forth in this Agreement.

         NOW, THEREFORE, in consideration of the mutual covenants and agreements
contained in this Agreement, and for other valuable consideration the receipt
and sufficiency of which are hereby acknowledged, the Servicer, the
Subservicers, and the Transferors hereby agree as follows:

         1. Definitions. Capitalized terms used herein and not otherwise defined
shall have the meanings set forth in the Pooling and Servicing Agreement, a copy
of which has been delivered by the Servicer to each Subservicer.
<PAGE>

         2. Servicing Compensation Relating to the Transferors' Interest. As
compensation for servicing and administering the Receivables allocated to the
Transferors' Interest pursuant to the Pooling and Servicing Agreement, the
Transferors shall pay to the Servicer, in immediately available funds on each
Distribution Date, a servicing fee in an amount equal to one-twelfth of the
product of (i) 2% and (ii) the Transferor Amount as of the last day of the
Monthly Period preceding such Distribution Date.

         3. Engagement of the Subservicers. Pursuant to Section 3.01 of the
Pooling and Servicing Agreement, the Servicer hereby engages (i) Centurion to
subservice and administer the Receivables arising in the Accounts owned by
Centurion (the "Centurion Receivables") and (ii) FSB to subservice and
administer the Receivables arising in the Accounts owned by FSB (the "FSB
Receivables"). Each of Centurion and FSB hereby accepts such engagement.

         4. Subservicing Fees. (a) As compensation for subservicing and
administering the Centurion Receivables in accordance with this Agreement, the
Servicer shall pay to Centurion, in immediately available funds on each
Distribution Date, a subservicing fee in an amount equal to $1000 (the
"Centurion Subservicing Fee"). As compensation for subservicing and
administering the FSB Receivables in accordance with this Agreement, the
Servicer shall pay to FSB, in immediately available funds on each Distribution
Date, a subservicing fee in an amount equal to $1000 (the "FSB Subservicing
Fee," and together with the Centurion Subservicing Fee, the "Subservicing
Fees"). Each Subservicing Fee may be adjusted from time to time to reflect such
factors as the Servicer and the applicable Subservicer mutually agree will
result in a Subservicing Fee determined to be fair consideration for the
subservicing and administrative obligations performed by such Subservicer.

         (b) Payment of the Subservicing Fees shall be independent of, and shall
not be conditioned in any way on, the receipt by the Servicer of the Servicing
Fee under the Pooling and Servicing Agreement or the servicing compensation
described in Section 2 of this Agreement.

         5. Duties of the Subservicers. (a) As agent for the Servicer, each
Subservicer shall take all actions reasonably requested by the Servicer to
subservice and administer the applicable Receivables, to collect and deposit
into the Collection Account payments due under such Receivables and to
charge-off as uncollectible such Receivables, in each case in accordance with
the Pooling and Servicing Agreement, the applicable Account Agreements, the
applicable Credit Guidelines, and such Subservicer's customary and usual
servicing procedures for servicing credit or charge receivables comparable to
such Receivables. As agent for the Servicer, each Subservicer shall have full
power and authority, acting alone or through the Servicer, to do any and all
things in connection with such subservicing and administration which it may deem
necessary or desirable and which is permitted of the Servicer under the Pooling
and Servicing Agreement.

         (b) No Subservicer shall be obligated to use separate servicing
procedures, offices, employees, or accounts for subservicing the applicable
Receivables from the procedures, offices, employees, and accounts used by such
Subservicer in connection with servicing other comparable receivables. Each
Subservicer may commingle Collections on the applicable Receivables to the
extent permitted of the Servicer under the Pooling and Servicing Agreement.

         (c) The Servicer shall furnish each Subservicer with any files,
records, or documents necessary or appropriate to enable such Subservicer to
carry out its subservicing and administrative duties hereunder. Each Subservicer
shall furnish the Servicer with any files, records, or documents necessary or
appropriate to enable the Servicer to carry out its servicing and administrative
duties under the Pooling and Servicing Agreement.

                                       2
<PAGE>

         (d) Each Subservicer shall pay out of its own funds, without
reimbursement, all expenses incurred in connection with its subservicing
activities hereunder.

         (e) Each Subservicer shall duly satisfy all obligations on its part to
be fulfilled under or in connection with each applicable Receivable and the
related Account, will maintain in effect all qualifications required under
Requirements of Law in order to subservice properly each applicable Receivable
and the related Account, and will comply in all material respects with all other
Requirements of Law in connection with subservicing each applicable Receivable
and the related Account, the failure to comply with which would have an Adverse
Effect.

         (f) No Subservicer shall authorize any rescission or cancellation of
any Receivable except in accordance with the applicable Credit Guidelines or as
ordered by a court of competent jurisdiction or other Governmental Authority.

         (g) No Subservicer shall take any action which, or omit to take any
action the omission of which, would impair the rights of the Trustee in any
Receivable. No Subservicer shall reschedule, revise, or defer payments due on
any Receivable except in accordance with the applicable Credit Guidelines, nor
shall it sell any assets in the Trust.

         (h) Except in connection with its enforcement or collection of an
Account, no Subservicer shall take any action to cause any Receivable to be
evidenced by any instrument (as defined in the UCC).

         (i) As reasonably requested by the Servicer, each Subservicer shall (i)
furnish the Servicer with true and complete copies of all reports, statements,
certificates, notices, and other documents received or generated by such
Subservicer in connection with its duties hereunder and (ii) cooperate with the
Servicer in taking any and all actions which the Servicer deems necessary in
order for it to satisfactorily perform its obligations under the Pooling and
Servicing Agreement. Nothing in this Agreement shall be construed as granting to
a Subservicer any right or power with respect to the Receivables that is more
expansive than that granted to the Servicer under the Pooling and Servicing
Agreement.

         6. Reimbursement of the Servicer. Each Subservicer, severally and not
jointly, shall reimburse the Servicer for any loss arising from a claim or
demand (including any claim for damages and any demand to accept an assignment
of Receivables) that is made against the Servicer under the Pooling and
Servicing Agreement and that arises from such Subservicer's misconduct,
negligence, or failure to abide by the terms of this Agreement (including
provisions of the Pooling and Servicing Agreement made applicable by this
Agreement).

         7. Representations, Warranties, and Covenants of the Parties. Each
party, for and as to itself only, hereby makes the following representations,
warranties, and covenants for the benefit of the other parties:

         (a) Such party is and will remain a legal entity duly organized and
validly existing in good standing under the laws of the jurisdiction of its
organization. Such party has, in all material respects, full power and authority
to own its properties and conduct its business as presently owned or conducted.
Such party has and will have, in all material respects, full power and authority
to execute, deliver, and perform its obligations under this Agreement.

                                       3
<PAGE>

         (b) Such party is and will remain duly qualified to do business, is and
will remain in good standing as a foreign entity (or is exempt from such
requirements), and has obtained and will retain all necessary licenses and
approvals, in each jurisdiction in which its obligations under this Agreement
require such qualification, except where the failure to so qualify or obtain
licenses or approvals would not have a material adverse effect on its ability to
perform its obligations under this Agreement.

         (c) Such party's execution, delivery, and performance of this Agreement
have been duly authorized by all necessary action on the part of such party.

         (d) This Agreement constitutes a legal, valid, and binding obligation
of such party, enforceable in accordance with its terms, except as such
enforceability may be limited by applicable bankruptcy, insolvency, or other
similar laws affecting creditors' rights generally or by general principles of
equity.

         (e) The execution and delivery of this Agreement by such party, and the
performance by such party of the transactions contemplated by this Agreement,
and the fulfillment by such party of the terms hereof and thereof applicable to
such party, will not conflict with, violate or result in any breach of any of
the material terms and provisions of, or constitute (with or without notice or
lapse of time or both) a material default under, any indenture, contract,
agreement, mortgage, deed of trust, or other instrument to which such party is a
party or by which it or its properties are bound.

         (f) The execution and delivery of this Agreement by such party, the
performance by such party of the transactions contemplated by this Agreement,
and the fulfillment by such party of the terms hereof and thereof applicable to
such party, will not conflict with or violate any Requirements of Law applicable
to such party.

         (g) There are no proceedings or investigations pending or, to the best
knowledge of such party, threatened against such party before any Governmental
Authority seeking to prevent the consummation of any of the transactions
contemplated by this Agreement or seeking any determination or ruling that, in
the reasonable judgment of such party, would materially and adversely affect the
performance by such party of its obligations under this Agreement.

         (h) All authorizations, consents, orders, or approvals of or
registrations or declarations with any Governmental Authority required to be
obtained, effected, or given by such party in connection with the execution and
delivery of this Agreement by such party, and the performance of the
transactions contemplated by this Agreement by such party, have been duly
obtained, effected, or given and are and will remain in full force and effect.

                                       4
<PAGE>

         8. Resignation or Termination of a Subservicer. A Subservicer may
resign at any time upon at least 45 days prior written notice to the Servicer.
The Servicer may terminate a Subservicer at any time upon at least 45 days prior
written notice to such Subservicer. The Servicer also may terminate a
Subservicer at any time without prior notice if (i) such Subservicer fails to
perform its obligations hereunder or (ii) any event occurs which materially and
adversely affects the ability of such Subservicer or the Servicer to collect the
applicable Receivables, the ability of such Subservicer to perform its
obligations hereunder, or the ability of the Servicer to perform its obligations
under the Pooling and Servicing Agreement.

         9. Term. Except as provided in Section 8 of this Agreement, this
Agreement shall continue in full force and effect until the earlier of (i) the
termination of the Servicer under the Pooling and Servicing Agreement or (ii)
the termination of the Pooling and Servicing Agreement.

         10. Notices. All notices, requests, and other communications permitted
or required hereunder shall be in writing and shall be delivered personally or
mailed by certified mail, postage prepaid and return receipt requested, or by
telex or facsimile as follows:

         If to the Servicer, addressed to:

         American Express Travel Related Services Company, Inc.
         American Express Tower
         World Financial Center
         200 Vesey Street
         New York, New York 10285
         Attn:  Treasurer (facsimile no. (212) 619-7099),

         If to Centurion, addressed to

         American Express Centurion Bank
         4315 South 2700 West
         Salt Lake City, Utah 84184
         Attn:  President (facsimile no. (801) 945-4075),

         If to FSB, addressed to

         American Express Bank, FSB
         4315 South 2700 West, 02-01-58
         Salt Lake City, Utah 84184
         Attn:  President (facsimile no. (801) 945-4050),

         If to RFC III, addressed to:

         American Express Receivables Financing Corporation III LLC
         4315 South 2700 West
         Room 1300, 02-01-04
         Salt Lake City, Utah 84184
         Attn:  President (facsimile no. (801) 945-4075),

         with a copy to American Express Travel Related Services Company, Inc.,
         as administrator, American Express Tower, World Financial Center, 200
         Vesey Street, New York, New York 10285, Attention: General Counsel
         (facsimile no. 212-619-7099),

                                       5
<PAGE>

         If to RFC IV, addressed to:

         American Express Receivables Financing Corporation IV LLC
         4315 South 2700 West
         Room 1100, 02-01-58
         Salt Lake City, Utah 84184
         Attn:  President (facsimile no. (801) 945-4050),

         with a copy to American Express Travel Related Services Company, Inc.,
         as administrator, American Express Tower, World Financial Center, 200
         Vesey Street, New York, New York 10285, Attention: General Counsel
         (facsimile no. 212-619-7099), and

         If to RFC II, addressed to

         American Express Receivables Financing Corporation II
         American Express Tower
         World Financial Center, Room 138
         200 Vesey Street
         New York, New York 10285-4405
         Attn:  Secretary (facsimile no. (212) 619-9261),

         with a copy to American Express Travel Related Services Company, Inc.,
         as administrator, American Express Tower, World Financial Center, 200
         Vesey Street, New York, New York 10285, Attention: General Counsel
         (facsimile no. 212-619-7099),

or to such other place within the United States of America as any party may
designate as to itself by written notice to the other parties. All notices given
by personal delivery or mail shall be effective on the date of actual receipt at
the appropriate address. Notice given by telex or facsimile shall be effective
upon actual receipt if received during the recipient's normal business hours or
the beginning of the next business day after receipt if received after the
recipient's normal business hours.

         11. Non-Petition Covenant. The Servicer and each Subservicer hereby
covenants and agrees that it will not at any time institute against any
Transferor, or join in instituting against any Transferor, any case or
proceeding under the United States Bankruptcy Code or any other bankruptcy,
insolvency, or similar law.

         12. Successors and Assigns. This Agreement shall be binding on the
parties hereto and their respective successors and assigns; provided, however,
that no Subservicer may assign any of its rights or delegate any of its duties
hereunder without the prior written consent of the Servicer.

         13. Severability. The provisions of this Agreement are intended to be
severable. If any provision of this Agreement shall be held invalid or
unenforceable in whole or in part in any jurisdiction, such provision shall, as
to such jurisdiction, be ineffective to the extent of such invalidity or
unenforceability without in any manner affecting the validity or enforceability
of such provision in any other jurisdiction or the remaining provisions hereof
in any jurisdiction.

                                       6
<PAGE>

         14. Counterparts. This Agreement may be executed in any number of
counterparts, all of which taken together shall constitute one and the same
instrument, and any of the parties hereto may execute this Agreement by signing
any such counterpart.

         15. GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO ITS
CONFLICTS OF LAW PROVISIONS, AND THE OBLIGATIONS, RIGHTS, AND REMEDIES OF THE
PARTIES HEREUNDER SHALL BE DETERMINED IN ACCORDANCE WITH SUCH LAWS.

         16. Captions. The captions in this Agreement are for convenience of
reference only and shall not define or limit any of the terms or provisions
hereof.

         17. Entire Agreement; Amendments; Waiver. This Agreement constitutes
the entire agreement of the parties on the subject matter addressed herein and
supersedes any other agreement of the parties on such subject matter. This
Agreement may not be amended, and no rights hereunder may be waived, except by a
written document signed by the duly authorized representatives of the parties.
No waiver of any of the provisions of this Agreement shall be deemed to be or
shall constitute a waiver of any other provisions hereof (whether or not
similar), nor shall such waiver constitute a continuing waiver unless otherwise
expressly provided.

            [The remainder of this page is left blank intentionally.]

                                       7
<PAGE>



                  IN WITNESS WHEREOF, the parties hereto have caused this
Agreement to be duly executed as of the day and year first above written.


                                      AMERICAN EXPRESS TRAVEL RELATED
                                      SERVICES COMPANY, INC.


                                      By:
                                           -------------------------------------
                                           Name:
                                           Title:


                                      AMERICAN EXPRESS CENTURION BANK


                                      By:
                                           -------------------------------------
                                           Name:
                                           Title:


                                      AMERICAN EXPRESS BANK, FSB


                                      By:
                                           -------------------------------------
                                           Name:
                                           Title:


                                      AMERICAN EXPRESS RECEIVABLES
                                      FINANCING CORPORATION III LLC


                                      By:
                                           -------------------------------------
                                           Name:
                                           Title:


                                      AMERICAN EXPRESS RECEIVABLES
                                      FINANCING CORPORATION IV LLC


                                      By:
                                           -------------------------------------
                                           Name:
                                           Title:


                                       8
<PAGE>



                                      AMERICAN EXPRESS RECEIVABLES
                                      FINANCING CORPORATION II


                                      By:
                                           -------------------------------------
                                           Name:
                                           Title:


                                       9