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                                                                    EXHIBIT 5(a)





                                                     May 26, 2000


FleetBoston Financial Corporation
One Federal Street
Boston, Massachusetts 02110

Ladies and Gentlemen:

         We have examined the Registration Statement on Form S-3 (the
"Registration Statement") to be filed by FleetBoston Financial Corporation (the
"Company") with the Securities and Exchange Commission on the date hereof in
connection with the registration under the Securities Act of 1933, as amended,
of (i) shares of common stock, $0.01 par value, including the associated
preferred share purchase rights (the "Common Stock"); (ii) shares of preferred
stock, $1.00 par value (the "Preferred Stock"), including, at the Company's
option, depositary shares (the "Depositary Shares") evidenced by depositary
receipts (the "Depositary Receipts") each representing a fractional interest in
such Preferred Stock; (iii) warrants to purchase Common Stock (the "Common Stock
Warrants") or Preferred Stock (the "Preferred Stock Warrants"); (iv) warrants to
purchase or sell securities of an entity unaffiliated with the Company, a basket
of such securities, an index or indices of such securities, currencies or
commodities (the "Universal Warrants"); (v) debt securities (the "Debt
Securities"), which may be either senior (the "Senior Debt Securities"), or
subordinated (the "Subordinated Debt Securities") in priority of payment; and
(vi) warrants to purchase Debt Securities (the "Debt Warrants", together with
Common Stock Warrants, Preferred Stock Warrants and the Universal Warrants, the
"Warrants" and together with the Common Stock, Preferred Stock, Depositary
Shares and Debt Securities, collectively, the "Securities") having a public
offering price of up to an aggregate of $3,951,868,750 (or the equivalent
thereof if any of the securities are denominated in a foreign currency or a
foreign currency unit) pursuant to an offering to be made on a continuous or
delayed basis pursuant to the provisions of Rule 415. The Securities may be
offered separately or as units with other Securities, in separate series, in
amounts and at prices and terms to be set forth in an accompanying prospectus
supplement.

         We have served as counsel for the Company and, as such, assisted in the
organization thereof under the laws of the State of Rhode Island and are
familiar with all corporate proceedings since its organization. We have examined
the following documents and records:


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FleetBoston Financial Corporation
May 26, 2000
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         (1) The Restated Articles of Incorporation of the Company; as amended
to date

         (2) The By-Laws of the Company, as amended to date;

         (3) The Senior Indenture dated as of December 23, 1999 between the
Company and The Bank of New York, as Senior Trustee, under which Senior Debt
Securities will be issued;

         (4) The Subordinated Indenture dated as of December 23, 1999 between
the Company and The Bank of New York, as Subordinated Trustee, under which
Subordinated Debt Securities will be issued;

         (5) Specimen certificate of the Common Stock and proposed forms of the
Preferred Stock certificates, the Depositary Receipts and the notes to be issued
evidencing the Debt Securities;

         (6) The proposed forms of the Warrant Agreements to be entered into by
the Company, pursuant to which the Warrants will be issued;

         (7) The proposed forms of the Warrants to be issued by the Company;

         (8) The proposed form of the Deposit Agreement to be entered into by
the Company, pursuant to which the Depositary Shares will be issued; and

         (9) All corporate minutes and proceedings of the Company relating to
the issuance of the Securities being registered under the Registration
Statement.

         We have also examined such further documents, records and proceedings
as we have deemed pertinent in connection with the issuance of said Securities.
In our examination, we have assumed the genuineness of all signatures, the legal
capacity of natural persons, the completeness and authenticity of all documents
submitted to us as originals, and the conformity to the originals of all
documents submitted to us as certified, photostatic or conformed copies, and the
validity of all laws and regulations. We also are familiar with the additional
proceedings proposed to be taken by the Company in connection with the
authorization, registration, issuance and sale of the Securities, and have
assumed that the Warrant Agreements, the Warrants, the Preferred Stock
Certificates, the Deposit Agreement, the Depositary Receipts, and the Notes are
duly executed and delivered in substantially the forms reviewed by us.

         We are qualified to practice law in the State of Rhode Island and we do
not purport to express any opinion herein concerning any law other than the laws
of the State of Rhode Island and the federal law of the United States.


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FleetBoston Financial Corporation
May 26, 2000
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         Based upon such examination, subject to the proposed additional
proceedings being duly taken and completed as now contemplated by the Company
prior to the issuance of the Securities, it is our opinion that:

         1. The Common Stock, Preferred Stock and Depositary Shares being
registered by the Registration Statement, when issued and paid for, will be
legally issued, fully paid and non-assessable.

         2. The Warrants, when issued and paid for, will be legally issued and
binding obligations of the Company except as enforcement may be limited by
bankruptcy, insolvency, reorganization, moratorium or similar laws, or equitable
principles relating to or limiting creditors' rights generally. We express no
opinion as to the availability of equitable remedies.

         3. The Debt Securities, when issued and paid for, will be legally
issued and binding obligations of the Company except as enforcement may be
limited by bankruptcy, insolvency, reorganization, moratorium or similar laws,
or equitable principles relating to or limiting creditors' rights generally. We
express no opinion as to the availability of equitable remedies.

         V. Duncan Johnson, a partner of Edwards & Angell, LLP is a director of
Fleet Bank (RI), National Association, a subsidiary of the Company, and
beneficially owns 9,856 shares of Common Stock of the Company.

         We consent to the use of this opinion as an exhibit to the Registration
Statement and to the reference to our firm in the Prospectus which is part of
the Registration Statement. In giving this consent, we do not thereby admit that
we are within the category of persons whose consent is required under Section 7
of the Securities Act of 1933, as amended, or the rules and regulations of the
Commission promulgated thereunder.


                                                Very truly yours,


                                                /s/ Edwards & Angell, LLP
                                                --------------------------------
                                                Edwards & Angell, LLP


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