EXHIBIT 10.21
             Severance Agreement and Mutual General Release between
                     NBT Bancorp Inc. and John W. Reuther.






                 SEVERANCE AGREEMENT AND MUTUAL GENERAL RELEASE


         This is a Severance Agreement and Mutual General Release ("Agreement")
between NBT Bancorp, Inc. ("NBTB") and John W. Reuther ("Executive").  In
consideration of the mutual promises and commitments made herein, and intending
to be legally bound hereby, NBTB and Executive agree as follows:

         1. Effective at 11:59p.m. on January 26, 2001, Executive has elected to
retire  and  resign  voluntarily  from all  positions  he holds as an officer of
NBTB's  Pennsylvania  banking  operations,  which is (or will be) doing business
under the name of Pennstar Bank,  N.A., and in accordance with the provisions of
his employment  agreement,  dated July 1, 2000.  Executive further  acknowledges
that, as a result of his retirement,  his employment  relationship with NBTB and
Pennstar  Bank will be  permanently  and  irrevocably  severed and that NBTB and
Pennstar Bank will have no obligation,  contractual  or otherwise,  to rehire or
reinstate him after January 26, 2001.

         2. NBTB and Executive agree that the Executive may continue,  after his
retirement, to serve as a director of Pennstar Bank, N.A. Furthermore, after the
effective date of the merger of Pennstar  Bank,  N.A. with and into Nystar Bank,
N.A.,  NBTB and  Executive  agree that the  Executive  may  continue as the Vice
Chairman  and a  director  of  Pennstar  Bank,  which  will be the  Pennsylvania
division of Nystar Bank,  N.A. As such,  Executive  shall be entitled to receive
directors'  fees and  other  such  compensation  as set by NBTB.  The  Executive
understands and agrees that he will not be a member of the Board of Directors of
Nystar Bank, N.A. after its merger with Pennstar Bank, N.A.

         3.  NBTB  agrees  to pay  Executive  by wire  transfer  in  immediately
available  funds to an account  designated  by  Executive on January 26, 2001 or
seven (7) days after  execution  of this  Agreement by  Executive,  whichever is
later, the following:

         A.       one million two hundred thousand dollars ($1,200,000); and
         B.       an amount equal to Executive's normal bonus payout under his
                  existing employment agreement for the calendar year
                  2000, if not received prior to January 26, 2001.

         Furthermore,  NBTB will transfer title to the automobile currently used
by  Executive  on January  26,  2001 or seven (7) days after  execution  of this
Agreement  by  Executive,  whichever  is later,  and will  continue in force the
medical health  insurance  benefit  program for Executive,  that is in effect on
January 26, 2001, until Executive reaches the age of sixty-two (62) years.

         Executive  will also be entitled  to receive no later than  January 26,
2001,  a grant of stock  options  pursuant to the NBT Bancorp,  Inc.  1993 Stock
Option Plan in accordance with his existing employment agreement.




         NBTB shall pay the  membership  fee for the  Executive  in the Elmhurst
Country  Club for the years  2001,  2002 and 2003.  NBTB shall not pay any other
expenses  incurred by the  Executive in  connection  with his  activities at the
Elmhurst Country Club.

         4. Executive acknowledges and agrees that, except for the payment under
paragraphs 3A and 3B, he is responsible  for the payments of all federal,  state
and local estimated quarterly income tax payments for the blue-book value of the
automobile as determined by NBTB.

         5. Nothing in this Agreement shall affect Executive's vested portion of
his account in NBTB's employee benefit and retirement programs.  Nothing in this
Agreement  shall  affect  Executive's  rights  under the Pioneer  American  Bank
Executive  Retirement Plan, dated October 25, 1988 (effective back to January 1,
1988) or the Split Dollar  Agreement,  dated April 16, 1999.  NBTB and Executive
agree that the terms and provisions of Executive's current employment  agreement
shall  remain in full force and effect up to and  including  January  26,  2001,
except that Executive  agrees to renounce any right to the payment of any salary
to him for the  period  from  January 1 to  January  26,  2001 and any  vacation
accrual that may be earned for the  calendar  year 2001 and in exchange for such
renouncement,  NBTB shall award the  Executive,  on December 31, 2000,  eighteen
additional vacation days to be used by the Executive in January 2001. NBTB shall
pay the Executive for these  vacation days at his current rate of  compensation.
Executive specifically acknowledges that this current employment agreement shall
be null and void as of January 27, 2001.

         6.A.  Executive  acknowledges that certain business  methods,  creative
techniques, and technical data of NBTB, its subsidiaries, and its affiliates and
the  like  are  deemed  by  NBTB to be and  are in  fact  confidential  business
information  of NBTB,  its  subsidiaries  or its  affiliates or are entrusted to
third  parties.  Such  confidential  information  includes but is not limited to
procedures, methods, sales relationships developed while in the service of NBTB,
its   subsidiaries  or  its   affiliates,   knowledge  of  customers  and  their
requirements,  marketing plans, marketing information,  studies,  forecasts, and
surveys,  competitive  analyses,  mailing  and  marketing  lists,  new  business
proposals, lists of vendors,  consultants,  and other persons who render service
or  provide  material  to  NBTB,  its  subsidiaries  or  their  affiliates,  and
compositions,  ideas,  plans, and methods belonging to or related to the affairs
of NBTB, its  subsidiaries,  or their affiliates.  In this regard,  NBTB asserts
proprietary  rights  in  all  of  its  business  information  and  that  of  its
subsidiaries  or  affiliates,  except for such  information as is clearly in the
public  domain.  Notwithstanding  the  foregoing,   information  that  would  be
generally known or available to persons  skilled in Executive's  fields shall be
considered  to be  "clearly  in the  public  domain"  for  the  purposes  of the
preceding sentence. Executive agrees that he will not disclose or divulge to any
third  party,  except  as may be  required  by his  duties  hereunder,  by  law,
regulation, or order of a court or government authority, or as directed by NBTB,
nor shall he use to the detriment of NBTB, its  subsidiaries,  or its affiliates
or use  in any  business  or on  behalf  of any  business  competitive  with  or
substantially  similar  to any  business  of NBTB,  its  subsidiaries,  or their
affiliates any confidential  business  information obtained during the course of
his employment with NBTB, its  subsidiaries  or affiliates.  The foregoing shall



not be construed as restricting  Executive from disclosing  such  information to
the employees of NBTB, its subsidiaries, or their affiliates.

         B.  Executive  hereby  agrees that from January 27, 2001 to January 26,
2003,  Executive will not (i) engage in the business activities that NBTB or any
of its  subsidiaries  and affiliates  are engaged in on January 27, 2001,  other
than on behalf of NBTB, its subsidiaries or their  affiliates  within the Market
Area (as hereinafter defined); (ii) directly or indirectly own, manage, operate,
control,  be employed by, or provide  management or  consulting  services in any
capacity  to any firm,  corporation,  or other  entity  (other  than  NBTB,  its
subsidiaries or their affiliates)  engaged in the banking business in the Market
Area; or (iii) directly or indirectly solicit or otherwise  intentionally  cause
any person known to Executive to be an employee, officer, or member of the Board
of Directors of Nystar Bank,  N.A. or a director of Pennstar Bank, a division of
Nystar Bank, N.A. or any of their affiliates to engage in any action  prohibited
under (i) or (ii) of this paragraph 6B; provided that the ownership by Executive
as an investor of not more than five percent of the outstanding  shares of stock
of any  corporation,  or the  shares of any  investment  company  as  defined in
section 3 of the Investment Company Act of 1940, as amended, shall not in itself
constitute a violation of Executives obligations under this paragraph 6B.

         C.  Executive  acknowledges  and agrees  that  irreparable  injury will
result  to  NBTB in the  event  of a  breach  of any of the  provisions  of this
paragraph 6 (the  "Designated  Provisions")  and that NBTB will have no adequate
remedy at law with  respect  thereto.  Accordingly,  in the event of a  material
breach of any  Designated  Provision,  and in  addition  to any  other  legal or
equitable  remedy  NBTB may  have,  NBTB  shall be  entitled  to the  entry of a
preliminary and permanent injunction  (including,  without limitation,  specific
performance)  by  a  court  of  competent  jurisdiction  in  Lackawanna  County,
Pennsylvania,  or  elsewhere,  to restrain the  violation  or breach  thereof by
Executive,  and Executive  submits to the jurisdiction of such court in any such
action.

         D. It is the desire and intent of the parties  that the  provisions  of
this paragraph 6 shall be enforced to the fullest extent  permissible  under the
laws and public policies  applied in each  jurisdiction in which  enforcement is
sought.  Accordingly,  if any particular  provision of this paragraph 6 shall be
adjudicated  to be  invalid or  unenforceable,  such  provision  shall be deemed
amended  to delete  therefrom  the  portion  thus  adjudicated  to be invalid or
unenforceable, such deletion to apply only with respect to the operation of such
provision in the particular  jurisdiction in which such adjudication is made. In
addition,  should any court  determine  that the  provisions of this paragraph 6
shall be unenforceable with respect to scope, duration, or geographic area, such
court shall be empowered to substitute,  to the extent  enforceable,  provisions
similar  hereto or other  provisions  so as to provide to NBTB,  to the  fullest
extent permitted by applicable law, the benefits intended by this paragraph 6.

         E.  As used  herein,  "Market  Area"  shall  mean  the  area  or  areas
delineated  by  circles  formed by radii  extending  twenty-five  miles from (i)
Scranton,  Pennsylvania,  (ii) the authorized branches of Pennstar Bank, N.A. or
Pennstar Bank, a division of Nystar Bank,  N.A., as the case may be, as they may
exist  from time to time,  and (iii)  each  branch of a  depository  institution



affiliated with NBTB for which Executive has or has had significant executive or
managerial responsibilities.

         7. If all or any portion of the amounts payable to Executive under this
Agreement,  either alone or together with other payments which Executive has the
right to receive from NBTB,  constitute  "excess parachute  payments" within the
meaning of Section 280G of the  Internal  Revenue Code of 1986 (the "Code") that
are  subject  to the excise  tax  imposed  by  Section  4999 of the Code (or any
successor  sections),  NBTB shall increase the amounts payable  hereunder to the
extent  necessary to place Executive in the same after-tax  position as he would
have been in had no such excise tax been imposed on the payments hereunder.  The
determination  of the  amount  of any  such  excise  taxes  shall be made by the
independent accounting firm retained by NBTB.

                  If  at a  later  date  it is  determined  (pursuant  to  final
regulations  or  published  rulings of the  Internal  Revenue  Service  ("IRS"),
assessment by the IRS or  otherwise)  that the amount of excise taxes payable by
Executive is greater than the amount  initially so  determined,  then NBTB shall
pay  Executive an amount equal to the sum of (A) such  additional  excise taxes,
plus (B) any  interest,  fines and  penalties  with  respect to such  additional
excise  taxes,  plus (C) the amount  necessary  to reimburse  Executive  for any
income,  excise or other taxes payable by Executive  with respect to the amounts
specified  in (A) and (B) above and the  reimbursement  provided  by this clause
(C).

         8. In consideration for NBTB's commitments hereunder,  Executive hereby
remises,  releases and forever  discharges NBTB and each and all of its past and
present subsidiaries, parent and related corporations,  companies and divisions,
and its past and present directors,  trustees, officers, managers,  supervisors,
employees, attorneys, and agents, and their predecessors, successors and assigns
(referred to  collectively in this Agreement as  "Releasees"),  from any and all
claims,  debts,  agreements,   complaints  or  causes  of  action  (hereinafter,
collectively, "claims"), whether known or unknown, that he ever had, now has, or
hereafter can, shall or may have against any or all of the Releasees, for, upon,
or by reason of any cause,  matter,  thing or event whatsoever  occurring at any
time from the date of  Executive's  birth up to and including  January 26, 2001.
Executive  acknowledges  and understands  that the claims being released in this
paragraph include, but are not limited to: (i) any claim based on contract or in
tort or common law; (ii) any claim based on or arising under any civil rights or
employment  discrimination  laws,  such as the  Federal  Age  Discrimination  in
Employment Act (29 U.S.C. ss. 621 ET SEQ.) (hereinafter,  "ADEA"),  Title VII of
the Civil Rights Act of 1964 (42 U.S.C.  ss. 2000e ET seq.), or the Pennsylvania
Human  Relations  Act (42 P.S.  ss.  951 ET SEQ.);  (iii) any claim  based on or
arising under any employment related law, such as the Employee Retirement Income
Security Act of 1974, as amended (29 U.S.C.  ss. 301 ET SEQ.), the Equal Pay Act
(29 U.S.C. ss. 201 ET SEQ.), the Americans With  Disabilities Act (42 U.S.C. ss.
12101 ET SEQ.),  the Family and Medical Leave Act (29 U.S.C.  ss. 2601 ET SEQ.),
or the Fair Labor  Standards Act, as amended (29 U.S.C.  ss. 201 ET SEQ.);  (iv)
any claim based on or arising out of Executive's employment by NBTB and Pennstar
Bank and their  predecessors  and/or his  resignation  therefrom  including  any
claims  pursuant to his  employment  agreement  dated July 1, 2000; and (iv) any



claims for compensatory,  liquidated or punitive damages,  damages for emotional
distress,  back pay,  front pay, and benefits.  In addition,  effective upon the
eighth day following  execution of this Agreement by Executive,  Executive shall
have hereby waived any and all claims,  whether  known or unknown,  that he ever
had, now has, or hereafter  can,  shall or may have under the  Change-in-Control
Agreement, as that term is defined in the Executive's employment agreement dated
July 1, 2000. Executive  understands that, by signing this Agreement,  he waives
all claims he ever had, now has, or may have against any of the Releasees.  NBTB
does hereby  remise,  release and forever  discharge  Executive from any and all
claims,  debts,  agreements,  complaints,  liabilities,  payments,  accountings,
actions and causes of action, whatsoever,  whether known or unknown, at the date
and time Executive executes this Agreement,  that NBTB does, shall or might have
against Executive,  for, upon or by reason of any cause,  matter, thing or event
whatsoever  occurring  at any time  from the  date of  Executive's  birth to and
including the date and time he executes this Agreement.  NBTB understands  that,
by the  execution of this  Agreement by an authorized  officer,  NBTB waives all
claims it ever had, now have, or may have against Executive,  including, but not
limited to, claims arising out of his  employment  prior to the date and time he
executes this  Agreement.  This release does not apply to the  requirements  and
obligations contained within this Agreement.

         9.  Executive  further  covenants  and  agrees  not to  sue  any of the
Releasees  for any claims  released  hereunder,  nor to assert  any such  claims
against  any of the  Releasees  for any  purpose.  Any claim for a breach of any
provision  of this  Agreement  may be remedied  only by a lawsuit to enforce the
Agreement and will not invalidate any party's release of claims.

         10. Executive agrees that the terms of this Agreement are confidential,
and that he will not  disclose or publicize  the terms of this  Agreement or the
amounts  paid or agreed to be paid  pursuant to this  Agreement to any person or
entity, except to his attorney or accountant,  or to a government agency for the
purposes of the payment or collection of taxes or application  for  unemployment
compensation.  NBTB agrees that the terms of this Agreement are confidential and
they will not  knowingly  disclose  or  publicize  (or  knowingly  permit  their
employees to disclose or  publicize)  the terms of this  Agreement or the amount
paid pursuant to this  Agreement to any person or entity except their  officers,
directors, attorneys or accountants, or to a government agency or representative
thereof;  provided,  however,  that  NBTB  does not  guarantee  that none of its
employees  will not  make  any such  disclosure  or  publication;  and  provided
further, that NBTB reserves the right to disclose the terms of this Agreement in
any  filing  required  under  the rules and  regulations  promulgated  under the
Securities  Exchange  Act of  1934 by the  Securities  and  Exchange  Commission
("SEC") if, in the opinion of NBTB's counsel,  such disclosure is required under
such rules and regulations of the SEC.

         11. All executed  copies of this Agreement,  and  photocopies  thereof,
shall  have the same  force and  effect  and  shall be as  legally  binding  and
enforceable as the original.

         12. All provisions of this Agreement are severable,  and if any of them
is  determined  to be invalid or  unenforceable  for any reason,  the  remaining



provisions and portions of this Agreement shall be unaffected  thereby and shall
remain in full force to the fullest extent permitted by law.

         13.  This  Agreement  is binding on  Executive  and on his  successors,
administrators, heirs and assigns, and inures to the benefit of each of NBTB and
the   Releasees   and  their   successors,   predecessors,   heirs,   executors,
administrators or assigns, as the case may be.

         14.  Executive  acknowledges  that he has been advised of his rights to
consult  with an attorney  before  signing this  Agreement  and that he has been
encouraged  to do so.  Consequently,  he has  been  represented  by  independent
counsel in this matter.

         15. Executive makes the following  additional  representations to NBTB,
each  of  which  is  significant  and  an  important  consideration  for  NBTB's
willingness to enter into the Agreement:

                  A.       Executive expressly acknowledges that if he did not
execute the Agreement, he would not be entitled to receive the money set forth
in paragraph 3 A.

                  B.  Executive  acknowledges  that he has been given a full and
fair  opportunity to review the Agreement.  NBTB  specifically  recommended that
Executive  consult with an attorney before  executing the Agreement,  and he has
been  allowed  up to  twenty-one  (21) days to  consider  whether  to accept the
Agreement.  Executive acknowledges that he is signing this Agreement voluntarily
and of his own free will, with full knowledge of the nature and  consequences of
its terms.

                  C.  Executive  understands  that he may change  his mind,  not
retire and revoke the  Agreement  at any time during the seven (7) days after he
signs the Agreement,  provided he does so in writing,  in which case none of the
provisions of the Agreement will have any effect.  Executive understands that he
will not be entitled to receive any payments under the Agreement until the seven
(7) day revocation period has expired without revocation of the Agreement.

         16. By entering into this Agreement, NBTB does not admit that it or any
of its employees  violated any law or any legal right of Executive and, in fact,
NBTB expressly denies liability. NBTB is entering into this Agreement solely for
the  purpose of  effectuating  a mutually  satisfactory  retirement  benefit for
Executive  and,  therefore,  Executive's  termination  of his  positions,  as an
officer of NBTB and the Pennstar Bank, N.A.

         17. By entering into this Agreement, neither Executive, nor NBTB admits
that he or they, or any of their  employees,  violated any law or legal right of
the other,  and,  in fact,  Executive,  and NBTB  expressly  deny  liability  or
responsibility.  They are entering into this Agreement solely for the purpose of
effectuating a mutual satisfactory severance of Executive's employment with, and
termination of his positions as an officer of NBTB.



         18. The Agreement and all acts and transactions  contemplated hereunder
shall be governed,  construed and interpreted in accordance with the laws of the
Commonwealth of Pennsylvania, without regard to principles of conflict of laws.

         19.      Each party shall be responsible for its own attorneys' fees.



         20.      This is the complete and final agreement between the parties
and supersedes all prior or contemporaneous agreements, employment offers,
negotiations or retirement discussions.



                                           NBT BANCORP, INC.


By:  /S/ John W. Reuther                   By:  /S/ Daryl R. Forsythe
     John W. Reuther                       Daryl R. Forsythe,
                                           President and Chief Executive Officer
     Date:  November 10, 2000              Date:  November __, 2000