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                                                                    EXHIBIT 8.1



                                CARLTON FIELDS
                               ATTORNEYS AT LAW

        ONE HARBOUR PLACE                              MAILING ADDRESS:
777 S. HARBOUR ISLAND BOULEVARD             P.O. BOX 3239, TAMPA, FL 33601-3239
   TAMPA, FLORIDA 33602-5799               TEL (813) 223-7000 FAX (813) 229-4133

                                October 12, 1999


Northeast Bancorp
232 Center Street
Auburn, Maine 04210


NBN Capital Trust
c/o Northeast Bancorp
232 Center Street
Auburn, Maine 04210



Ladies and Gentlemen:

         We have acted as counsel to Northeast Bancorp, a Maine corporation
(the "Company"), and to NBN Capital Trust, a Delaware statutory business trust
(the "Trust"), in connection with the registration statement of the Company and
the Trust on Form S-2 (the "Registration Statement"), of which a prospectus
("Prospectus") is a part, filed by the Company and the Trust with the United
States Securities and Exchange Commission under the Securities Act of 1933, as
amended (the "Securities Act"). This opinion is furnished pursuant to the
requirements of Item 601(b)(8) of Regulation S-K promulgated under the
Securities Act.

         For the purposes of rendering this opinion, we have reviewed and
relied upon the Registration Statement and such other documents and instruments
as we deemed necessary for the rendering of this opinion. In our examination of
relevant documents, we have assumed the legal capacity of all natural persons,
genuineness of all signatures on original documents, the authenticity of all
documents submitted to us as originals, the conformity to original documents of
all documents submitted to us as copies, the authenticity of such copies, and
the accuracy and completeness of all corporate records made available to us by
the Company and the Trust. We

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Northeast Bancorp
NBN Capital Trust
October 12, 1999
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also have assumed the authority of such persons signing on behalf of the
parties thereto other than the Company or the Trust, the due authorization,
execution, and delivery of all documents by parties thereto other than the
Company or the Trust.

         Based solely on (a) the foregoing and (b) our review of such documents
and upon such information as the Company has provided to us (which we have not
attempted to verify in any respect), and in reliance upon such documents and
information, subject to the qualifications hereinafter expressed, we are of the
opinion that the statements contained in the Prospectus under the caption
"Certain Federal Income Tax Consequences" describing certain federal income tax
consequences to holders of the Preferred Securities, as qualified therein,
constitute an accurate description in general terms of the indicated United
States federal income tax consequences to such holders.

         Our opinion is limited to the federal income tax matters described
above and does not address any other federal income tax considerations or any
state, local, foreign, or other tax considerations. If any of the information
on which we have relied is incorrect, or if changes in the relevant facts occur
after the date hereof, our opinion could be affected thereby. Moreover, our
opinion is based on the Internal Revenue Code of 1986, as amended, applicable
Treasury regulations promulgated thereunder, and Internal Revenue Service
rulings, procedures, and other pronouncements published by the United States
Internal Revenue Service. These authorities are all subject to change, and such
change may be made with retroactive effect. We can give no assurance that,
after such change, our opinion would not be different. We undertake no
responsibility to update or supplement our opinion. This opinion is not binding
on the Internal Revenue Service, and there can be no assurance, and none is
hereby given, that the Internal Revenue Service will not take a position
contrary to one or more of the positions reflected in the foregoing opinion, or
that our opinion will be upheld by the courts if challenged by the Internal
Revenue Service.

         We are attorneys admitted to practice in the State of Florida and,
accordingly, we express no opinion with respect to matters governed by the laws
of any jurisdiction other than the federal laws of the United States or the
internal laws of the State of Florida, and we assume no responsibility as to
the applicability of the laws of any other jurisdiction to the subject matter
hereof or to the effects of such laws thereon.

         This opinion is rendered to you and for your benefit solely in
connection with the filing of the Registration Statement. This opinion may not
be relied upon by you for any other purpose and may not be relied upon by, nor
may copies thereof be provided to, any other person, firm, corporation or
entity for any purpose whatsoever without our prior written consent. We hereby
consent to the filing of this opinion as an exhibit to the Registration
Statement. We also consent to the use of our name in the Prospectus under the
caption "Certain Federal Income Tax

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Northeast Bancorp
NBN Capital Trust
October 12, 1999
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Consequences." Unless prior written consent of our firm is obtained, this
opinion is not to be quoted or otherwise referred to in any report, proxy
statement or other registration statement, nor is it to be filed with or
furnished to any other governmental agency or any person, except as otherwise
required by law.



                                             Sincerely,

                                             CARLTON, FIELDS, WARD, EMMANUEL,
                                                SMITH & CUTLER, P.A.


                                             By: /s/ Richard A. Denmon
                                                -------------------------------
                                                     Richard A. Denmon