<PAGE>

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                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

                               ----------------
                                 Amendment #1

                                      TO

                                   FORM 10-K

      FOR ANNUAL AND TRANSITION REPORTS PURSUANT TO SECTIONS 13 OR 15(d)
                    OF THE SECURITIES EXCHANGE ACT OF 1934

[X]ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
   ACT OF 1934

                                      OR

[_]TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
   EXCHANGE ACT OF 1934

                  For the fiscal year ended December 26, 1999
                        Commission File Number 0-24543

                               COST-U-LESS, INC.
            (Exact Name of Registrant as Specified in its Charter)

<TABLE>
<S>                                                         <C>
                 Washington                                      91-1615590
        (State or Other Jurisdiction                          (I.R.S. Employer
      of Incorporation or Organization)                     Identification No.)
</TABLE>

              12410 S.E. 32nd Street, Bellevue, Washington 98005
             (Address of Principal Executive Offices): (Zip Code)

                                (425) 644-4241
             (Registrant's Telephone Number, Including Area Code)

          Securities registered pursuant to Section 12(b) of the Act:

                                     None

          Securities registered pursuant to Section 12(g) of the Act:

                                 Common Stock
                  Cumulative Preference Shares, First Series

                               ----------------

  Indicate by check mark whether the registrant: (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to
such filing requirements for the past 90 days. Yes [X] No [_]

  Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to
the best of the registrant's knowledge, in definitive proxy or information
statements incorporated by reference in Part III of this Form 10-K or any
amendment to this Form 10-K. [_]

  The aggregate market value of the voting and nonvoting stock held by non-
affiliates of the registrant at March 18, 2000 was approximately $5,912,000.

  The number of shares of the registrant's Common Stock outstanding at March
18, 2000 was 3,576,858.


                      DOCUMENTS INCORPORATED BY REFERENCE

  The information required by Part III of this Report, to the extent not set
forth herein, is incorporated herein by reference from the Registrant's
definitive proxy statement relating to the annual meeting of stockholders to
be held on May 18, 2000, which definitive proxy statement shall be filed with
the Securities and Exchange Commission within 120 days after the end of the
fiscal year to which this Report relates.

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<TABLE>
<CAPTION>
  Exhibit
    No.                                 Description
  -------                               -----------
 <C>        <S>
  10.25***  Rights Agreement dated March 15, 1999 between the Company and
            ChaseMellon Shareholder Services, L.L.C., as rights agent
  10.26**** Lease Agreement between Caribe Lumber & Trading N.V. (St. Maarten)
            and the Company, dated February 19, 1999
  10.27     Sublease Agreement between New Breed Distribution Corp. of
            California, Inc. and the Company dated November 1, 1999.
  10.28     Lease Agreement between AMB Property, L.P., and the Company dated
            December 2, 1999.
  10.29     Lease Agreement between Pukeroa Oruawhata Holdings Limited and the
            Company dated February 17, 2000.
  10.30     Lease Agreement between North Gate Park Limited and the Company
            dated December 9, 1999.
 +23.1      Consent of Ernst & Young LLP, Independent Auditors
  24.1      Power of Attorney (see page 45).
 +27.1      Financial Data Schedule
</TABLE>
--------
*     Incorporated by reference to the Company's Registration Statement on Form
      S-1 (Registration No. 333-52459).

**    Incorporated by reference to the Company's Quarterly Report on Form 10-Q
      dated September 2, 1998.

***   Incorporated by reference to the Company's Registration Statement on Form
      8-A dated March 15, 1999.

****  Incorporated by reference to the Company's Annual Report on Form 10-K
      dated March 26, 1999.

+     previously filed

  (b) Reports on Form 8-K:

    None.

                                       44
<PAGE>

                                  SIGNATURES

  Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the Company has duly caused this Report to be signed on
its behalf by the undersigned, thereunto duly authorized.

                                          COST-U-LESS, INC.

Date: April 5, 2000                               /s/ J. Jeffrey Meder
                                          By: _________________________________
                                                      J. Jeffrey Meder
                                                       President and
                                                  Chief Executive Officer

  Each person whose individual signature appears below hereby authorizes and
appoints J. Jeffrey Meder and Roy W. Sorensen, and each of them, with full
power of substitution and resubstitution and full power to act without the
other, as his or her true and lawful attorney-in-fact and agent to act in his
or her name, place and stead and to execute in the name and on behalf of each
person, individually and in each capacity stated below, and to file, any and
all amendments to this Report, and to file the same, with all exhibits
thereto, and other documents in connection therewith, with the Securities and
Exchange Commission, granting unto said attorneys-in-fact and agents, and each
of them, full power and authority to do and perform each and every act and
thing, ratifying and confirming all that said attorneys-in-fact and agents or
any of them or their or his or her substitute or substitutes may lawfully do
or cause to be done by virtue thereof.

  Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the Company
and in the capacities indicated below on the 5th day of April, 2000.

<TABLE>
<CAPTION>
             Signature                                  Title
             ---------                                  -----
<S>                                  <C>
      /s/ Michael J. Rose            Chairman of the Board
------------------------------------
          Michael J. Rose

      /s/ J. Jeffrey Meder           President and Chief Executive Officer
------------------------------------  (Principal Executive Officer)
          J. Jeffrey Meder

      /s/ Roy W. Sorensen            Vice President, Chief Financial Officer,
------------------------------------  Secretary and Treasurer (Principal
          Roy W. Sorensen             Financial and Accounting Officer)

       /s/ David A. Enger            Director
------------------------------------
           David A. Enger

      /s/ Wayne V. Keener            Director
------------------------------------
          Wayne V. Keener

      /s/ Gary W. Nettles            Director
------------------------------------
          Gary W. Nettles

      /s/ George C. Textor           Director
------------------------------------
          George C. Textor
</TABLE>

                                      45