Exhibit 5


                                Bingham Dana LLP
                               150 Federal Street
                                Boston, MA 02110


                                April 3, 2001

Century Bancorp, Inc.
400 Mystic Avenue
Medford, Massachusetts  02155

   Re:  Registration Statement on Form S-8
        2000 Stock Option Plan

Ladies and Gentlemen:

     This opinion is furnished in connection with the registration, pursuant to
a Registration Statement on Form S-8 under the Securities Act of 1933, as
amended (the "Act"), to be filed with the Securities and Exchange Commission on
or about April 3, 2001 (the "Registration Statement"), of 150,000 shares (the
"Shares") of Class A common stock, par value $1.00 per share (the "Class A
Common Stock"), of Century Bancorp, Inc., a Massachusetts corporation (the
"Company"), which are or will be issuable to employees and directors of the
Company upon the exercise of options granted pursuant to the Company's 2000
Stock Option Plan (the "2000 Plan").

     We have acted as counsel to the Company in connection with the foregoing
registration of the Shares. We have examined and relied upon originals or
copies of such records, instruments, certificates, memoranda and other
documents as we have deemed necessary or advisable for purposes of this opinion
and have assumed, without independent inquiry, the accuracy of those documents.
In that 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
such documents. We have further assumed that all options granted or to be
granted pursuant to the 2000 Plan were or will be validly granted in accordance
with the terms of the 2000 Plan and that all Shares to be issued upon exercise
of such options will be issued in accordance with the terms of such options and
the 2000 Plan.

     This opinion is limited solely to the laws of The Commonwealth of
Massachusetts, as applied by courts located in Massachusetts and the Delaware
General Corporation Law, as applied by courts located in Delaware, 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, upon
the issuance and delivery of the Shares in accordance with the terms of such
options and the 2000 Plan, the Shares will be validly issued, fully paid and
non-assessable shares of the Company's Class A Common Stock.

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

                                       Very truly yours,


                                       /s/ BINGHAM DANA LLP
                                       BINGHAM DANA LLP