EXHIBIT 5.1

March 25, 2002


Costco Wholesale Corporation
999 Lake Drive
Issaquah, Washington  98027

Re:  Costco Wholesale Corporation - Public Offering of 5 1/2% Senior Notes
     Due March 15, 2007

Ladies and Gentlemen:

     We have acted as  counsel to Costco  Wholesale  Corporation,  a  Washington
corporation (the  "Company"),  in connection with the filing by the Company with
the  Securities and Exchange  Commission  (the  "Commission")  of a Registration
Statement on Form S-3 (File No. 333-01127) and a Registration  Statement on Form
S-3 (File No. 333-72122)  (together,  the "Registration  Statement") pursuant to
the  Securities  Act of 1933,  as amended (the  "Securities  Act"),  as declared
effective under the Securities Act, and the related  prospectus  dated March 20,
2002, as supplemented by a prospectus supplement dated March 20, 2002 (the final
prospectus, in the form filed with the Commission pursuant to Rule 424(b) of the
rules and regulations under the Act, the "Prospectus"), relating to the offering
by the Company of $300,000,000  aggregate  principal amount of its 5 1/2% Senior
Notes Due  March 15,  2007 (the  "Securities").  The  Securities  will be issued
pursuant to a Senior Debt  Securities  Indenture  dated October 26, 2001 and the
First  Supplemental  Indenture  dated March 20, 2002,  each  between  U.S.  Bank
National   Association,   as  Trustee,  and  the  Company   (collectively,   the
"Indenture").

                                       I.

     We have assumed the authenticity of all records,  documents and instruments
submitted to us as  originals,  the  genuineness  of all  signatures,  the legal
capacity of natural  persons and the conformity to the originals of all records,
documents and instruments  submitted to us as copies.  We have based our opinion
upon  our  review  of  the  following   records,   documents,   instruments  and
certificates and such additional  certificates relating to factual matters as we
have deemed necessary or appropriate for our opinion:

     (a)  The Registration Statement;


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     (b)  The Indenture;

     (c)  The Prospectus;

     (d)  The Securities;

     (e)  The Amended and  Restated  Articles of  Incorporation  (including  all
          amendments  thereto)  of  the  Company  certified  by  the  Washington
          Secretary  of State as of March 21,  2002,  and  certified to us by an
          officer of the Company as being  complete and in full force and effect
          as of the date of this opinion;

     (f)  A  Certificate  of  Existence  relating to the  Company  issued by the
          Washington Secretary of State, dated March 21, 2002;

     (g)  The Bylaws of the Company (and all amendments thereto) certified to us
          by an officer of the Company as being  complete  and in full force and
          effect as of the date of this opinion;

     (h)  Records  certified to us by an officer of the Company as  constituting
          all records of  proceedings  and actions of the board of  directors of
          the Company relating to the issuance of the Securities by the Company;
          and

     (i)  A  certificate  (the  "Officer's  Certificate")  of an  officer of the
          Company as to certain factual matters.

                                       II.

     This  opinion  is  limited  to the  federal  laws of the  United  States of
America,  the laws of the State of Washington,  and the laws of the State of New
York, and we disclaim any opinion as to the laws of any other  jurisdiction.  We
express no opinion as to the applicable  choice of law rules that may affect the
interpretation or enforcement of the Securities. We further disclaim any opinion
as to any statute, rule, regulation,  ordinance,  order or other promulgation of
any  regional  or  local  governmental  body or as to any  related  judicial  or
administrative opinion.

                                      III.

     Based upon the foregoing and our examination of such questions of law as we
have deemed necessary or appropriate for the purpose of our opinion, and subject
to the limitations and  qualifications  expressed herein, it is our opinion that
the Securities, when


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                                                                  March 25, 2002
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sold and after receipt of payment therefor,  will be legally issued,  fully paid
and  non-assessable  and will  constitute  valid and binding  obligations of the
Company,  enforceable  against  the  Company in  accordance  with  their  terms,
subject,  as to  enforcement,  (i) to  bankruptcy,  insolvency,  reorganization,
arrangement,  moratorium and other laws of general applicability  relating to or
affecting  creditors' rights and (ii) to general  principles of equity,  whether
such enforceability is considered in a proceeding in equity or at law.

                                       IV.

     We further advise you that:

     A.   As noted,  the  enforceability  of the  Securities  is  subject to the
          effect of general  principles  of equity.  These  principles  include,
          without limitation, concepts of commercial reasonableness, materiality
          and good faith and fair dealing.  As applied to the Securities,  these
          principles will require the parties thereto to act reasonably, in good
          faith  and in a manner  that is not  arbitrary  or  capricious  in the
          administration and enforcement of the Securities and will preclude the
          parties  thereto from  invoking  penalties  for defaults  that bear no
          reasonable  relation to the damage  suffered  or that would  otherwise
          work a forfeiture.

     B.   The  enforceability of the Securities is subject to the effects of (i)
          Section 1-102 of the New York Uniform  Commercial  Code (the "New York
          UCC"),  which  provides  that  obligations  of good faith,  diligence,
          reasonableness  and  care  prescribed  by the New  York UCC may not be
          disclaimed  by  agreement,  although  the  parties  may  by  agreement
          determine the standards by which the  performance of such  obligations
          is to be measured if those standards are not manifestly  unreasonable,
          (ii) Section 1-203 of the New York UCC, which imposes an obligation of
          good faith in the  performance  or enforcement of a contract and (iii)
          legal  principles  under which a court may refuse to  enforce,  or may
          limit the  enforcement of, a contract or any clause of a contract that
          a court  finds as a matter of law to have been  unconscionable  at the
          time it was made.

     C.   The effectiveness of indemnities, rights of contribution,  exculpatory
          provisions and waivers of the benefits of statutory  provisions may be
          limited on public policy grounds.

     D.   Provisions of the Securities requiring that waivers must be in writing
          may not be binding or  enforceable if a  non-executory  oral agreement
          has been created
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          modifying any such provision or an implied agreement by trade practice
          or course of conduct has given rise to a waiver.


                                       V.

     We hereby  consent  to the  filing of this  opinion  as an  exhibit  to the
Current Report of the Company on Form 8-K and to the Registration  Statement and
to the  reference  to this  firm  under  the  heading  "Legal  Opinions"  in the
Prospectus or any supplement  thereto  constituting  a part of the  Registration
Statement.

     This  opinion  is  rendered  to you in  connection  with the  filing of the
Current Report of the Company on Form 8-K and is solely for your benefit and the
benefit of the purchasers of the Securities. This opinion may not be relied upon
by any other person, firm, corporation or other entity without our prior written
consent.  We  disclaim  any  obligation  to advise you of any change of law that
occurs, or any facts of which we become aware, after the date of this opinion.

                                Very truly yours,


                                Heller Ehrman White & McAuliffe LLP

















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