NBT Bancorp Inc. & BSB Bancorp, Inc.

                                Merger of Equals

                                 April 20, 2000













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Forward Looking Statement
- -------------------------

This  presentation  contains  statements  regarding  NBT  Bancorp  Inc.  and BSB
Bancorp, Inc. following the completion of the merger of equals discussed herein,
including strategies,  plans and objectives, as well as estimates and statements
based on underlying  estimates of future  financial  condition,  performance and
operating  efficiencies  on a pro  forma  basis  and cost  savings  and  revenue
enhancements  and accretion to reported  earnings that will be realized from the
merger.

These statements and estimates constitute forward-looking statements (within the
meaning of the Private Securities  Litigation Reform Act of 1995), which involve
significant  risks and  uncertainties.  A variety of factors  could cause actual
results and experience to differ materially from forward-looking statements.

Factors  that might  cause such a  difference  include,  but are not limited to,
risks and uncertainties related to the consummation of the merger, including the
realization of the level of revenues following the merger;  integration costs or
difficulties;  competition from both financial and  non-financial  institutions;
changes in interest rates, deposit flows, loan demand and accounting principles,
policies  or  guidelines;  the  timing and  occurrence  (or  non-occurrence)  of
transactions and events that may be subject to circumstances  beyond the control
of NBT or BSB; and other  economic,  competitive,  governmental,  regulatory and
technological   factors  affecting  NBT  or  BSB  or  the  combined  institution
specifically or the banking industry or economy generally.

Neither  NBT or BSB  assumes  any  obligation  to update  these  forward-looking
statements  or to update the reasons why actual  results could differ from those
projected in the forward-looking statement.

This document does not constitute an offer of any  securities  for sale.  Before
making  any  decision  with  respect  to  the  proposed  merger,   NBT  and  BSB
stockholders will be provided with a joint proxy statement/prospectus which will
be included in the  registration  statement to be filed with the  Securities and
Exchange  Commission by NBT. All such stockholders should read that registration
statement, including the proxy statement, before making any investment decision.


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PRESENTERS
- ----------

Daryl R.  Forsythe - Chairman  President  and CEO of NBT Bancorp Inc.
Thomas L. Thorn - Acting  President and CEO of BSB Bancorp,  Inc.
Michael J. Chewens - CFO of NBT Bancorp Inc.
Rexford C. Decker - CFO of BSB Bancorp, Inc.

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                               Transaction Summary

 Fixed Exchange Ratio:                   2.00 NBTB shares for each share of BSBN
 Exchange Rationale:                            Ownership for Earnings Basis
 Transaction Value at Announcement: (1)                 $251 million
 Accounting:                                     Pooling / Tax Free Exchange
 Due Diligence:                                          Completed
 Anticipated Expense Reduction:                     $7.4 million annually
 Expected Closing:                                  Fourth Quarter of 2000



(1) Based on NBT's April 19, 2000 closing price of $12.00


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Transaction Summary (continued)

 Holding Company Name:                        To Be Determined
 Bank Name:                                   To Be Determined
 Principal Office:                             Binghamton, NY
 Board of Directors: (1)          7 from BSB and 8 from NBT including 2 from the
                                        company's Pennsylvania subsidiary
 Chairman & CEO:                               Daryl R. Forsythe
 Estimated Merger Charge:                  $15 to 18 million pre-tax
 Cross-Options:                               19.9% priced at market
 Price Protection:                                  None

(1) Provided NBT's pending transaction with Pioneer American closes.


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Transaction Rationale

o        Exchange  ratio was based upon estimated  contributions  to earnings in
         future  periods  by  the  two  participants.  (excluding  non-recurring
         charges)

o        Expected to be  accretive  to earnings  per share for all  participants
         during 2001

0        Improves shareholder  liquidity with projected total shares outstanding
         of 44.9 million

o        Creates a more  visible  entity with  proforma  assets of $4.6  billion
         which should attract increased analyst coverage and increased  interest
         of institutional investors

o        Leverages strong competitive positions in adjacent markets

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Cost Saving Analysis

Non Interest Expense                            (In Millions)
- --------------------                            -------------
Salary & Benefits                                   $2.9
Occupancy Expense                                    0.3
Professional Fees / Outside Svcs.                    2.8
IS and Communications                                0.2
Other Operating Expenses                             1.2
                                                     ---
         Total                                      $7.4


Note: Full phase in expected in 2001.


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EPS Analysis of Cost Saves

Estimated  cost saves of $7.4  million  will  generate  approximately  $0.10 per
share(1) accretion once the cost saves have been fully implemented in 2001.

(1) Utilizes 44.9 million shares and an effective tax rate of 38%.


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Pro Forma Balance Sheet (in thousands)
- --------------------------------------
Data as of December 31, 1999

                                                                    Pro forma
                         NBT (1)         BSB                        Combined
                         -------         ---                        --------

Total Assets            2,378,408        2,240,948                  4,619,356
Securities                747,399          401,723                  1,149,122
Loans                   1,463,217        1,722,252                  3,185,469
Total Deposits          1,777,091        1,901,204                  3,678,295
Total Equity              189,763          154,493                    344,166

Shares Outstanding                                               44.9 million

(1) Includes pending acquisition of Pioneer American Holding Company.


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Financial Ratios
- ----------------
Based on annualized 4th qtr 1999 results

                                                              Proforma
                             NBT          BSB                 Combined
                             ---          ---                 --------
ROAA                          1.17       1.10                    1.13
ROAE                         12.56      15.26                   14.08
NIM                           4.82       4.23                    4.46
Efficiency Ratio             56.83      41.38                   47.66
Leverage Ratio                9.50       7.85                    8.47


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Overview of Combined Market Area
- --------------------------------

o        102 total branches serving 19 counties in 2 states
o        Commanding  market  presence in eight counties as measured by a deposit
         share rank of 1, 2, or 3
o        Leading deposit share in Binghamton and Norwich.
o        Growing presence in the Syracuse and Scranton markets


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                              [MAP OF MARKET AREA]





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Deposit Share and Rank by County
- --------------------------------

County, State                 Deposit             Rank
================================================================================
Broome, NY                    56.5%               1
- --------------------------------------------------------------------------------
Chemung, NY                   5.1%                6
- --------------------------------------------------------------------------------
Chenango, NY                  84.4%               1
- --------------------------------------------------------------------------------
Clinton, NY                   9.8%                4
- --------------------------------------------------------------------------------
Delaware, NY                  33.9%               1
- --------------------------------------------------------------------------------
Essex, NY                     25.0%               2
- --------------------------------------------------------------------------------
Fulton, NY                    11.1%               4
- --------------------------------------------------------------------------------
Montgomery, NY                2.0%                6
- --------------------------------------------------------------------------------
Oneida, NY                    5.3%                6
- --------------------------------------------------------------------------------
Onondaga, NY                  4.7%                7
- --------------------------------------------------------------------------------
Otsego, NY                    1.6%                7
- --------------------------------------------------------------------------------
Oswego, NY                    0.4%                11
- --------------------------------------------------------------------------------
Tioga, NY                     21.2%               2
- --------------------------------------------------------------------------------
Lackawanna, PA                11.5%               3
- --------------------------------------------------------------------------------
Luzerne, PA                   0.9%                16
- --------------------------------------------------------------------------------
Monroe, PA                    3.2%                6
- --------------------------------------------------------------------------------
Pike, PA                      18.6%               3
- --------------------------------------------------------------------------------
Wayne, PA                     17.9%               3
- --------------------------------------------------------------------------------
Wyoming,PA                    0.6%                6
================================================================================


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Summary of One Time Expenses



Charges                                     (In Millions)
- ---------                                   -------------
Professional Fees                                $7 to 8
Severance                                              3
Data Processing                                   3 to 5
Other                                                   2
                                                 -------
Total                                         $15 to $18


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Reasons to Invest in the New Company


o    Expected to be  accretive  to EPS in first full year
o    Similar  corporate cultures that will be easily integrated
o    Increased operating efficiencies
o    Building on each other's strength through cross selling opportunities


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