File No. 333-15521

   As filed with the Securities and Exchange Commission on February 7, 1997.

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                         POST-EFFECTIVE AMENDMENT NO. 1
                                       TO
                                    FORM S-4
                             REGISTRATION STATEMENT
                        UNDER THE SECURITIES ACT OF 1933

                                      AS A

                                    FORM S-8

                          REGISTRATION STATEMENT UNDER
                           THE SECURITIES ACT OF 1933

                                   UST CORP.
             (Exact name of Registrant as specified in its charter)

Massachusetts                                       04-2436093
(State or other jurisdiction                           (I.R.S. Employer
or incorporation or organization)                      Indemnification No.)

40 Court Street,                   Boston, MA                    02108
(Address of Principal Executive Offices)                          (Zip Code)

            The Co-operative Bank of Concord 1985 Stock Option Plan
     The Co-operative Bank of Concord 1987 Stock Option and Incentive Plan
     The Co-operative Bank of Concord 1995 Stock Option and Incentive Plan
       The Co-operative Bank of Concord 1993 Employee Stock Purchase Plan
          The Braintree Savings Bank 1985 Incentive Stock Option Plan
                           (Full titles of the Plans)

                             Eric R. Fischer, Esq.,
              Executive Vice President, General Counsel and Clerk
                                   UST Corp.
                                40 Court Street
                                Boston, MA 02108
                                 (617) 726-7377

____________________________________________________________________________
 (Name, address, including zip code and telephone number, including area code
                             of agent for service)

This Registration Statement previously registered 10,611,549 shares of common
stock, par value $0.625 per share (the "Common Stock"), of UST Corp. ("UST").
Effective January 3, 1997, 10,125,540 of such shares were issued upon the
consummation of UST's acquisition of Walden Bancorp, Inc. ("Walden"). This
Registration Statement now relates to the 486,009 previously registered shares
that were not issued in the acquisition of Walden which shall be issuable to
participants in the respective (i) The Co-operative Bank of Concord 1985 Stock
Option Plan, (ii) The Co-operative Bank of Concord 1987 Stock Option and
Incentive Plan, (iii) The Co-operative Bank of Concord 1995 Stock Option and
Incentive Plan, (iv) The Co-operative Bank of Concord 1993 Employee Stock
Purchase Plan, and (v) The Braintree Savings Bank 1985 Incentive Stock Option
Plan (collectively, the "Plans"), as such number may be increased in accordance
with the Plans in the event of a merger, consolidation, recapitalization or
similar event involving UST.





                                    PART II

                       INFORMATION REQUIRED IN PROSPECTUS
 
Item 3.  Incorporation of Documents by Reference

      The following documents filed by UST Corp. (the "Registrant") with the
Securities and Exchange Commission (the "SEC") are hereby incorporated by
reference in this Registration Statement: (1) the Registrant's latest annual
report filed pursuant to Section 13(a) or 15(d) of the Securities Exchange Act
of 1934, as amended (the "Exchange Act"); (2) all other reports filed by the
Registrant pursuant to Section 13(a) or 15(d) of the Exchange Act since the end
of the fiscal year covered by the annual report referred to in (a) above; and
(3) the description of the Common Stock contained in the Registrant's
Registration Statement filed under Section 12(g) of the Exchange Act, including
any amendment or report filed for the purpose of updating such description.

      In addition, all documents subsequently filed by the Registrant pursuant
to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act prior to the filing
of a post-effective amendment which indicates that all securities offered
hereby have been sold or which deregisters all of such securities then
remaining unsold, shall be deemed to be incorporated by reference into this
Registration Statement and to be a part hereof from the date of filing of such
documents.


Item 4.  Description of Securities

      A description of the Registrant's Common Stock to be offered is not
provided in this registration statement because such class of the Registrant's
securities is registered under Section 12 of the Exchange Act.


Item 5.  Interests of Named Experts or Counsel

      The validity of the shares of Common Stock offered herein has been passed
upon for the Registrant by Eric R. Fischer, General Counsel of the Registrant,
40 Court Street, Boston, Massachusetts 02108. Mr. Fischer is also an officer of
certain other subsidiaries of the Registrant. As of February 7, 1997, Mr.
Fischer had a direct or indirect interest in 36,663 shares of Common Stock and
had options to purchase an additional 50,800 shares, all of which were
immediately exercisable.


Item 6.  Indemnification of Directors and Officers

      Section 67 of Chapter 156B of the Massachusetts General Laws authorizes a
corporation to indemnify any director, officer, employee or other agent of the
corporation to whatever extent specified in or authorized by (a) the articles
of organization, (b) a by-law adopted by the stockholders or (c) a vote adopted



by the holders of a majority of the shares of stock entitled to vote on the
election of directors.

      The Registrant's Articles of Organization provide that the Registrant
shall, to the fullest extent legally permissible, indemnify each person who is
or was a director, officer, employee or other agent of the Registrant and each
person who is or was serving at the request of the Registrant as such of
another corporation or of any partnership, joint venture, trust, employee
benefit plan or other enterprise or organization, against all liabilities,
costs and expenses, including but not limited to amounts paid in satisfaction
of judgments, in settlement or as fines and penalties, and counsel fees and
disbursements, reasonably incurred by him or her in connection with the defense
or disposition of or otherwise in connection with or resulting from any action,
suit or other proceeding, whether civil, criminal, administrative or
investigative, before any court or administrative or legislative or
investigative body, in which he or she may be or may have been involved as a
party or otherwise or with which he or she may have been threatened, while in
office or thereafter, by reason of his or her being or having been such a
director, officer, employee, agent or trustee, or by reason of any action taken
or not taken in any such capacity. Under Massachusetts law and the Articles of
Organization, no indemnification may be provided for any person with respect to
any matter as to which he or she shall have been adjudicated in any proceeding
not to have acted in good faith in the reasonable belief that his or her action
was in the best interest of the Registrant or other entity served or, to the
extent that such matter relates to service with respect to an employee benefit
plan, in the best interest of the participants or beneficiaries of such
employee benefit plan.

      If, in an action, suit or proceeding brought by or in the name of the
Registrant, a director of the Registrant is held not liable for monetary
damages, whether because that director is relieved of personal liability under
the provisions of the Articles of Organization, or otherwise, that director
shall be deemed to have met the standard of conduct set forth above and to be
entitled to indemnification for expenses reasonably incurred in the defense of
such action, suit or proceeding.

      As to any matter disposed of by settlement pursuant to a consent decree
or otherwise, no indemnification either for the amount of such settlement or
for any other expenses shall be provided unless such settlement shall be
approved as in the best interests of the Registrant, after notice that it
involves such indemnification, (a) by vote of a majority of the disinterested
directors then in office (even though the disinterested directors be less than
a quorum), (b) by any disinterested person or persons to whom the question may
be referred by vote of a majority of such disinterested directors, or (c) by
vote of the holders of a majority of the outstanding stock at the time entitled
to vote for directors, voting as a single class, exclusive of any stock owned
by any interested person, or (d) by any disinterested person or persons to whom
the question may be referred by vote of the holders or a majority of such
stock. No such approval shall prevent the recovery from any such officer,
director, employee, agent or trustee of any amounts paid to him or her or on
his or her behalf as indemnification in accordance with the preceding sentence
if such person is subsequently adjudicated by a court of competent jurisdiction
not to have acted in good faith in the reasonable belief that his or her action
was in the best interest of the Registrant.

      The rights of indemnification provided in the Registrant's Articles of
Organization shall not be exclusive of or affect any other rights to which any
director, officer, employee, agent or trustee may be entitled or which may
lawfully be granted to him or her. Indemnification of a "director", "officer",



"employee", "agent", and "trustee" includes their respective executors,
administrators and other legal representatives. An "interested" person is one
against whom the action, suit or other proceeding in question or another
action, suit or other proceeding on the same or similar grounds is then or had
been pending or threatened, and a "disinterested" person is a person against
whom no such action, suit or other proceeding is then or had been pending or
threatened.


Item 7.  Exemption from Registration Claimed

      Not applicable.


Item 8.  Exhibits

      The following exhibits are part of this Registration Statement:

      3         Amendment to Articles of Organization of UST.

      5         Opinion and Consent of Eric R. Fischer, Esq., General Counsel 
                of UST, as to the validity of the shares of Common Stock.

      23.1      Consent of Eric R. Fischer (included in Exhibit 5).

      23.2      Consent of Arthur Andersen LLP (concerning UST financials).

      23.3      Consent of Arthur Andersen LLP (concerning Walden financials)

      24        Power of Attorney (previously filed).


                  [Remainder of page intentionally left blank]





                                   SIGNATURES

      Pursuant to the requirements of the Securities Act of 1933, the
Registrant certifies that it has reasonable grounds to believe that it meets
all of the requirements of filing on Form S-8 and has duly caused this
Registration Statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Boston, and The Commonwealth of Massachusetts,
on the 31st day of January, 1997.

                                      UST Corp.


                                      By:/s/ Eric R. Fischer
                                      	 Eric R. Fischer
                                         (Executive Vice President,
                                         General Counsel and Clerk)

      Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the dates indicated.

Signature                         Title                           Date

/s/ Neal F. Finnegan 			
______________________     President and Chief Executive      January 30, 1997
(Neal F. Finnegan)         Officer (Principal Executive
                           Officer) and Director

/s/ James K. Hunt
_________________________  Executive Vice President and       January 30, 1997
(James K. Hunt)            Treasurer (Principal Financial
                           Officer and Principal Accounting
                           Officer)

_________________________  Director                           January __, 1997
(Chester G. Atkins)

_________________________  Director                           January __, 1997
(David E. Bradbury)


           *               Director
_________________________
(Robert M. Coard)

/s/ Domenic Colasacco
_________________________  Director                           January 30, 1997
(Domenic Colasacco)


           *               Director
_________________________
(Robert L. Culver)







           *               Director
_________________________
(Alan K. DerKazarian)


           *               Director
_________________________
(Donald C. Dolben)


           *               Director
_________________________
(Edward Guzovsky)


           *               Director
_________________________
(Wallace M. Haselton)


           *               Director
_________________________
(Brian W. Hotarek)


_________________________  Director                           January __, 1997
(Francis X. Messina)


           *               Director
_________________________
(Sydney L. Miller)


           *               Director
_________________________
(Vikki L. Pryor)


           *               Director
_________________________
(Gerald M. Ridge)


           *               Director
_________________________
(William Schwartz)


_________________________  Director                           January __, 1997
Barbara C. Sidell)


_________________________  Director                           January __, 1997
(James V. Sidell)


_________________________  Director                           January __, 1997
(Paul D. Slater)





           *               Director
_________________________
(Edward J .Sullivan)


_________________________  Director                           January __, 1997
(G. Robert Tod)


           *               Director
_________________________
(Michael J. Verrochi, Jr.)


           *               Director
_________________________
(Gordon M. Weiner)

		
	    /s/ Eric R. Fischer
      *By:_______________________________                     January 30, 1997
      (Eric R. Fischer, Attorney-in-Fact)








                                 EXHIBIT INDEX

   Exhibit No.           Description of Documents

        3        Amendment to Articles of  Organization of
                 UST.

        5        Opinion and Consent of Eric R. Fischer,
                 General Counsel of UST, as to the
                 validity of the shares of Common Stock
                 being offered herein.

       23.1      Consent of Eric R. Fischer (included in Exhibit 5).      ---

       23.2      Consent of Arthur Andersen LLP (concerning 
                 UST financials).
       23.3      Consent of Arthur Andersen LLP (concerning 
                 Walden financials)
       24        Power of Attorney (previously filed).                    ---