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                                                                    EXHIBIT 10.4

                                SECOND AMENDMENT
                             TO EMPLOYMENT AGREEMENT

          SECOND AMENDMENT, dated as of May __, 2002 (this "Amendment"), to the
Employment Agreement referred to below among PATRIOT NATIONAL BANK, a national
banking association with headquarters located in Stamford, Connecticut (the
"BANK"), PATRIOT NATIONAL BANCORP, INC., a Connecticut corporation ("BANCORP")
and CHARLES F. HOWELL of Danbury, Connecticut (the "EXECUTIVE").

                               W I T N E S S E T H

          WHEREAS, Bank, Bancorp and the Executive are parties to that certain
Employment Agreement, dated as of October 23, 2000, as amended pursuant to that
certain First Amendment to Employment Agreement dated, as of March 21, 2001 (as
amended, the "EMPLOYMENT AGREEMENT"); and

          WHEREAS, there is an ambiguity in the provisions of Section 3(g)(ii)
of the Employment Agreement arising from the fact that a stock option plan
anticipated to be adopted by Bancorp has to date never been approved by the
Board of Directors and the shareholders of Bancorp, which stock option plan
would have provided for a four-year vesting schedule for stock options (25% per
year) in the same manner as provided for the Executive's stock grants pursuant
to Section (g)(i);

          WHEREAS, the parties have agreed to amend certain terms of the
Employment Agreement, in the manner, and on the terms and conditions, provided
for herein;

          NOW THEREFORE, in consideration of the premises and for other good and
valuable consideration, the receipt, adequacy and sufficiency of which are
hereby acknowledged, the parties hereby agree as follows:

1.    DEFINITIONS. Capitalized terms not otherwise defined herein shall have the
meanings ascribed to them in the Employment Agreement.

2.    AMENDMENT TO SECTION 3(g)(ii) OF THE EMPLOYMENT AGREEMENT. By way of
clarification, it is hereby expressly agreed that with respect to any grant of
stock options provided for in Section 3(g)(ii) of the Employment Agreement, the
options as to the first 25% of the shares covered by any such option grant shall
vest on the succeeding December 31st (an "Initial Vesting Date") (e.g., options
as to the first 25% of the shares covered by any grants on December 31, 2002
will vest on December 31, 2003) and options as to an additional 25% shall vest
on each of the first, second and third anniversary dates of such Initial Vesting
Date. In the event that the Board of Directors determines, in its reasonable
discretion, that any of said stock options for the Executive cannot be granted,
the remaining provisions of Section 3(g)(ii) shall continue to govern under such
circumstances.

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3.    NO OTHER AMENDMENTS. Except as expressly amended herein, the Employment
Agreement shall be unmodified and shall continue to be in full force and effect
in accordance with its terms. In addition, except as specifically provided
herein, this Amendment shall not be deemed a waiver of any term or condition of
the Employment Agreement and shall not be deemed to prejudice any right or
rights which either party may now have or may have in the future under or in
connection with the Employment Agreement or any of the instruments or agreements
referred to therein, as the same may be amended from time to time.

4.    COUNTERPARTS. This Amendment may be executed by the parties hereto on any
number of separate counterparts and all of said counterparts taken together
shall be deemed to constitute one and the same instrument.

          IN WITNESS WHEREOF, the parties hereto have caused this Amendment to
be duly executed and delivered as of the day and year first above written.

                                           PATRIOT NATIONAL BANK


                                           By: /s/ Angelo De Caro
                                               --------------------------------
                                               Name:
                                               Title:


                                           PATRIOT NATIONAL BANCORP, INC.


                                           By: /s/ Angelo De Caro
                                               --------------------------------
                                               Name:
                                               Title:


                                           /s/ Charles F. Howell
                                           ------------------------------------
                                           Charles F. Howell

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