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FOR IMMEDIATE RELEASE

ATTENTION: FINANCIAL AND BUSINESS EDITORS

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NBT Contact: Daryl R. Forsythe       Pioneer Contact: John W. Reuther
             607-337-6416                             570-282-2662

                                           Pursuant   to  Rule  425   under  the
                                           Securities  Act of  1933  and  deemed
                                           filed  pursuant to Rule 14a-12  under
                                           the Securities Exchange Act of 1934.

               PIONEER AMERICAN COMPLETES MERGER WITH NBT BANCORP

     CARBONDALE,  PA and NORWICH, NY (JUNE 23, 2000) - The Board of Directors of
Pioneer American Holding Company Corp., parent company of Pioneer American Bank,
N.A.,  gave final  approval to their  merger into NBT Bancorp Inc.  today.  This
action  follows  the  approval  of the  agreement  and  plan  of  merger  by the
stockholders of both companies at separate  meetings held earlier this week. The
merger is slated to close July 1, 2000.

     Ultimately  Pioneer  American  Bank will be combined with LA Bank to create
the  largest   independent   community  bank   headquartered   in   Northeastern
Pennsylvania.  LA Bank, based in Scranton, PA, joined NBT earlier this year as a
result of the merger of its parent company, Lake Ariel Bancorp,  Inc., into NBT.
The combination of these financial  institutions is slated for completion in the
fourth quarter of this year.  The resulting  bank will serve  customers in seven
counties  from 45  locations  and have pro forma  assets of  approximately  $1.1
billion.

     John W. Reuther,  President and CEO of Pioneer American Bank stated, "It is
exciting to see this  opportunity  come to fruition.  The combination of Pioneer
American  Bank and LA Bank will allow us to continue to offer the  residents  of
Northeastern  Pennsylvania a quality community  banking option.  Our affiliation
with NBT will enable our new bank to offer expanded services  including enhanced
lending  capabilities,  trust  services,  venture  capital  and other  financial
products.

     NBT  President  and CEO Daryl R.  Forsythe  commented,  "We are  pleased to
welcome Pioneer American into our growing company. The completion of this merger
is another  important  milestone in our efforts to create the  region's  premier
community banking and



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financial services company." NBT recently announced plans for a merger of equals
with BSB  Bancorp,  Inc. of  Binghamton,  NY.  This  merger,  currently  pending
regulatory  and  stockholder  approval,  is also expected to close in the fourth
quarter of 2000. It will create a financial  services  holding  company with pro
forma  assets  of   approximately   $4.8  billion  and  three  direct  operating
subsidiaries including two community banks and a financial services company.

     o  Pioneer  American  Bank  and LA Bank  will be  combined  to form the new
        company's Pennsylvania bank subsidiary.

     o  NBT Bank,  N.A.  and BSB Bank & Trust will be  combined  to form the new
        company's New York bank subsidiary.

     o  The third  direct  operating  subsidiary  will be a  financial  services
        company.  NBT  created  this  entity in  September  1999 to  expand  the
        company's  menu  of  financial  services  beyond   traditional   banking
        services.  When the NBT/BSB  merger is complete the  financial  services
        company will also encompass the trust and investment division.

     As  a  result  of  the  merger  with  Pioneer  American,   NBT  will  issue
approximately  5.2  million  shares  of its  common  stock to  Pioneer  American
stockholders. They will receive 1.805 shares of NBT common stock in exchange for
each  share  of  Pioneer  American  stock.  The  merger  is  accounted  for as a
pooling-of-interests  and qualifies as a tax-free  exchange for Pioneer American
stockholders.  Three  directors  from Pioneer  American's  board will join NBT's
Board of Directors.

Forward-Looking Information

This news release contains statements regarding the projected performance of NBT
Bancorp,  Pioneer  American  Bank, LA Bank and BSB Bancorp on a combined  basis.
These statements  constitute  forward-looking  information within the meaning of
the Private Securities  Litigation Reform Act of 1995. Actual results may differ
materially from the projections discussed in this release since such projections
involve  significant  risks and  uncertainties.  Factors that  might  cause such
differences  include,  but are  not  limited  to:  competitive  pressures  among
financial institutions  increasing  significantly;  economic conditions,  either
nationally or locally in areas in which NBT Bancorp,  Pioneer  American Bank, LA
Bank and BSB  Bancorp  conduct  their  operations,  being  less  favorable  than
expected; the cost and effort required to integrate aspects of the operations of
the companies being more difficult than expected; expected cost savings from



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the merger not being fully realized within the expected time frame;  legislation
or regulatory changes which adversely affect the ability of the combined company
to conduct its current or future  operations.  NBT disclaims  any  obligation to
update any such factors or to publicly  announce the result of any  revisions to
any of the  forward-looking  statements included herein to reflect future events
or developments.

     This press release may be deemed to be solicitation  material in respect of
the proposed merger of BSB Bancorp,  Inc.  ("BSB") with NBT Bancorp Inc. ("NBT")
pursuant to an  Agreement  and Plan of Merger,  dated as of April 19, 2000,  and
amended as of May 17, 2000, by and between NBT and BSB (the "Agreement"). Filing
of this press release is being made in connection  with  Regulation of Takeovers
and Security Holder Communications  (Release No. 33-7760,  34-42055) promulgated
by the Securities and Exchange Commission ("SEC").

     NBT  and  its  directors  and  executive  officers  may  be  deemed  to  be
participants  in the  solicitation  of proxies  in  respect of the  transactions
contemplated by the Agreement.  These directors and executive  officers  include
the following: Daryl R. Forsythe, Michael J. Chewens, Martin A. Dietrich, Joe C.
Minor, John D. Roberts,  Everett A. Gilmour, J. Peter Chaplin, Peter B. Gregory,
William C. Gumble,  Bruce D. Howe,  Andrew S.  Kowalczyk,  Jr., Dan B. Marshman,
John G. Martines, John C. Mitchell, William L. Owens and Paul O. Stillman. As of
March 31, 2000, these directors and executive officers beneficially owned in the
aggregate 1,417,878 shares, or approximately  7.83%, of NBT's outstanding common
stock.  Additional information about the directors and executive officers of NBT
is included in NBT's proxy statement for its 2000 Annual Meeting of shareholders
dated April 3, 2000.

     In  connection  with the  proposed  merger,  NBT will  file  with the SEC a
registration  statement on SEC Form S-4. The registration statement will contain
a joint proxy  statement/prospectus,  which will describe the proposed merger of
NBT and BSB and the proposed terms and conditions of the merger. Stockholders of
NBT  are  encouraged  to  read  the  registration   statement  and  joint  proxy
statement/prospectus  because these documents will contain important information
about the merger.  After the  registration  statement  is filed with the SEC, it
will be  available  for free,  both on the SEC's  web site  (www.sec.gov)  or by
contacting  NBT Bancorp Inc., 52 South Broad  Street,  Norwich,  New York 13815,
Attention: John D. Roberts, telephone (607) 337-6541.

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