AMENDMENT NO. 1 TO CUSTODY AGREEMENT

                                 AMENDMENT NO. 1
                                       TO
                                CUSTODY AGREEMENT

      This Amendment No. 1 (the "Amendment") to that certain Custody Agreement
dated as of December 8, 2003 between AIM Treasurer's Series Trust (the "Fund")
and The Bank of New York (the "Custodian") (hereinafter the "Custody Agreement")
is made as of May 31, 2005.

                                  WITNESSETH :

      WHEREAS, the Fund desires to execute an Agreement with XX Xxxxxx Xxxxx
Bank, N.A.;

      NOW, THEREFORE, the Fund and the Custodian hereby amend the Custody
Agreement as follows:

      1. Section 7 of Article XV is hereby renumbered Section 7(a).

      2. A new Section 7(b) is hereby added to Article XV to read in its
entirety as follows:

            "(b) Notwithstanding any other provision in this Agreement, the Fund
      shall appoint XX Xxxxxx Chase Bank, N.A. (the "Bank") by executing the
      form of Agreement attached hereto (the "Agreement"). The Fund agrees that
      notwithstanding any other provision in this Agreement: (1) the Custodian
      shall have no duty to supervise or monitor the Bank under the Agreement,
      nor shall the Custodian have any liability for the acts or omissions of
      the Bank, for its appointment, or for its receiving, holding, or
      disbursing any assets; and (2) without limiting the generality of the
      foregoing, the Fund shall indemnify and hold harmless the Custodian from
      and against any loss, liability, claim, expense or demand incurred by the
      Custodian relating to or arising out of the Agreement or the appointment
      or actions or omissions of the Bank. The provisions of this Section 7(b)
      shall survive any resignation of the Custodian or the terms of this
      Agreement."

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      IN WITNESS WHEREOF, the parties hereto have caused this Amendment No. 1 to
be executed by their respective officers, thereof to duly authorize as of the
day and year first above written.

                                       AIM TREASURER'S SERIES TRUST

                                       By: /s/ Xxxxxx X. Xxxxxxx
                                           -------------------------------------
                                           Name: Xxxxxx X. Xxxxxxx
                                           Title: Vice President and Treasurer

                                       THE BANK OF NEW YORK

                                       By: /s/ Xxxxxx X. XxXxxx
                                           -------------------------------------
                                           Name: Xxxxxx X. XxXxxx
                                           Title: Managing Director

Attest:

_______________________________

(seal)

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