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                                                                     Exhibit 5.1

                                November 18, 2003

Waters Corporation
34 Maple Street
Milford, MA 01757

Re:      Registration Statement on Form S-8 Under the Securities Act of 1933,
                  as amended

Dear Sir or Madam:

         We have acted as counsel for Waters Corporation, a Delaware corporation
(the "Company"), in connection with the Company's Registration Statement on Form
S-8 to be filed with the Securities and Exchange Commission on November 20, 2003
(the "Registration Statement").

         The Registration Statement covers the registration of 5,697,290 shares
of common stock, $0.01 par value per share, of the Company (the "Shares"), which
are to be issued by the Company pursuant to awards issued or to be issued
pursuant to Waters Corporation 2003 Equity Incentive Plan (the "Plan").

         We have reviewed the corporate proceedings of the Company with respect
to the authorization of the Plan and the issuance of the Shares thereunder. We
have also examined and relied upon originals or copies, certified or otherwise
identified or authenticated to our satisfaction, of such agreements,
instruments, corporate records, certificates, and other documents as we have
deemed necessary or appropriate as a basis for the opinions hereinafter
expressed. In our examination, we have assumed the genuineness of all
signatures, the conformity to the originals of all documents reviewed by us as
copies, the authenticity and completeness of all original documents reviewed by
us in original or copy form, and the legal competence of each individual
executing any document. As to all matters of fact (including factual conclusions
and characterizations and descriptions of purpose, intention or other state of
mind) we have relied entirely upon certificates of officers of the Company, and
have assumed, without independent inquiry, the accuracy of those certificates.

         We further assume that all Shares issued pursuant to awards granted or
to be granted pursuant to the Plan will be issued in accordance with the terms
of the Plan and that the purchase price of the Shares will be greater than or
equal to the par value per share of the Shares.

         This opinion is limited solely to the Delaware General Corporation Law,
the applicable provisions of the Delaware Constitution and the reported judicial
decisions interpreting those laws.

         Based upon and subject to the foregoing, we are of the opinion that the
Shares, when issued and delivered upon the exercise of options duly granted
pursuant to the Plan and against the payment of the purchase price therefor,
will be validly issued, fully paid, and non-assessable.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement.

                                            Very truly yours,

                                            /s/ Bingham McCutchen LLP

                                            BINGHAM MCCUTCHEN LLP

