COLUMBIA ACORN FUND
                          COLUMBIA ACORN INTERNATIONAL
                               COLUMBIA ACORN USA
                              COLUMBIA ACORN SELECT
                       COLUMBIA ACORN INTERNATIONAL SELECT
                            COLUMBIA THERMOSTAT FUND
                PROSPECTUS SUPPLEMENT DATED FEBRUARY 9, 2005 TO
                          PROSPECTUS DATED MAY 1, 2004

         As discussed in greater detail in earlier supplements, on March 15,
2004, Columbia Management Advisors, Inc. ("Columbia Management"), the advisor to
the Columbia Funds, and Columbia Funds Distributor, Inc. ("CFD" and collectively
with Columbia Management, "Columbia") the distributor of the shares of the
Columbia Funds, the Columbia Acorn Funds and the Wanger Advisors Trust Funds
(collectively, "the Columbia Family of Funds"), entered into agreements in
principle with the staff of the U.S. Securities and Exchange Commission ("SEC")
and the Office of the New York Attorney General ("NYAG") to resolve the
proceedings brought in connection with the SEC's and NYAG's investigations of
frequent trading and market timing in certain Columbia mutual funds. Columbia
Wanger Asset Management, L.P., the advisor to the Columbia Acorn Funds and the
Wanger Advisors Trust Funds, was not a respondent in either proceeding nor were
any of its officers or directors.

         On February 9, 2005, Columbia entered into an Assurance of
Discontinuance (the "NYAG Settlement") with the NYAG and consented to the entry
of a cease-and-desist order by the SEC (the "SEC Order" and together, the
"Settlements"). The Settlements contain substantially the same terms and
conditions as outlined in the agreements in principle. Although none of the
Columbia Acorn Funds is a party to the Settlement orders, under the terms of the
Settlements and in order for Columbia Management to continue to provide
administrative services to the Columbia Acorn Funds, the Board of Trustees of
the Columbia Acorn Funds expects to comply voluntarily with certain
requirements, including: the election of an independent board chairman, which
the Board had done well in advance of the regulatory proceedings; and the
appointment of one or more individuals to monitor legal compliance and to add
another level of assurance that the management fees to be charged to the Funds
are negotiated at arm's length and are reasonable.

         Under the terms of the SEC Order, Columbia has agreed, among other
things, to: pay $70 million in disgorgement and $70 million in civil money
penalties; cease and desist from violations of the antifraud provisions and
certain other provisions of the federal securities laws; maintain certain
compliance and ethics oversight structures; retain an independent consultant to
review Columbia's applicable supervisory, compliance, control and other policies
and procedures; and retain an independent distribution consultant (see below).
The NYAG Settlement also, among other things, requires Columbia and its
affiliates, Banc of America Capital Management, LLC and BACAP Distributors, LLC
to reduce management fees paid by the Columbia Family of Funds, Nations Funds
and other related mutual funds collectively by $32 million per year for five
years, for a projected total of $160 million in management fee reductions based
on net assets as of March 15, 2004. Pursuant to the procedures set forth in the
SEC Order, the settlement amounts will be distributed in accordance with a
distribution plan to be developed by an independent distribution consultant, who
is acceptable to the SEC staff and the independent trustees of the funds. The
distribution plan must be based on a methodology developed in consultation with
Columbia and the independent trustees of the funds and not unacceptable to the
staff of the SEC. More specific information on the distribution plan will be
communicated at a later date.

         As a result of these matters or any adverse publicity or other
developments resulting from them, including lawsuits brought by shareholders of
the affected Columbia Funds, there may be increased redemptions or reduced sales
of Fund shares, which could increase transaction costs or operating expenses, or
have other adverse consequences for the Columbia Funds.

         A copy of the SEC Order will be available on the SEC's website at
http://www.sec.gov. A copy of the NYAG Settlement will be available as part of
the Bank of America Corporation Form 8-K filing on or about February 10, 2005.



                              COLUMBIA ACORN TRUST

                               COLUMBIA ACORN FUND
                          COLUMBIA ACORN INTERNATIONAL
                               COLUMBIA ACORN USA
                              COLUMBIA ACORN SELECT
                       COLUMBIA ACORN INTERNATIONAL SELECT
                            COLUMBIA THERMOSTAT FUND
                    SUPPLEMENT DATED FEBRUARY 9, 2005 TO THE
              STATEMENT OF ADDITIONAL INFORMATION DATED MAY 1, 2004

Under the heading "PROGRAMS FOR ELIMINATING OR REDUCING SALES CHARGES", the
following is added:

PRIVILEGES OF INSURANCE COMPANY SEPARATE ACCOUNTS. Class A shares of the Funds
may be sold to insurance company separate accounts without the imposition of a
front-end sales charge provided that the following conditions are met:

     1.   The sponsoring insurance company makes shares of a Fund available to
          its contract owner/investors without the imposition of a sales charge;

     2.   The sponsoring insurance company provides services to the investors in
          the insurance company separate account, including recordkeeping and
          administrative services, for which the sponsoring insurance company
          would be compensated by the Trust's service providers and not by a
          Fund; and

     3.   The insurance company separate account is structured as a pool of IRA
          accounts managed by the sponsoring insurance company.



                                                                ACN-35/507U-0205