EXHIBIT 25.1

THIS CONFORMING PAPER FORMAT DOCUMENT IS BEING SUBMITTED PURSUANT TO RULE 901(d)
OF REGULATION S-T

================================================================================

                                    FORM T-1

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                            STATEMENT OF ELIGIBILITY
                   UNDER THE TRUST INDENTURE ACT OF 1939 OF A
                    CORPORATION DESIGNATED TO ACT AS TRUSTEE

                      CHECK IF AN APPLICATION TO DETERMINE
                      ELIGIBILITY OF A TRUSTEE PURSUANT TO
                             SECTION 305(b)(2) |__|

                           -------------------------

                              THE BANK OF NEW YORK
               (Exact name of trustee as specified in its charter)


New York                                                    13-5160382
(State of incorporation                                     (I.R.S. employer
if not a U.S. national bank)                                identification no.)

48 Wall Street, New York, N.Y.                              10286
(Address of principal executive offices)                    (Zip code)

                           -------------------------

                             ONBANK CAPITAL TRUST I
               (Exact name of obligor as specified in its charter)

Delaware                                                    To be applied for
(State or other jurisdiction of                             (I.R.S. employer
incorporation or organization)                              identification no.)

101 South Salina Street
P.O. Box 4983
Syracuse, New York                                          13221-4983
(Address of principal executive offices)                    (Zip code)

                           -------------------------

                               Capital Securities
                       (Title of the indenture securities)

================================================================================


1.  General information. Furnish the following information as to the Trustee:

    (a) Name and address of each examining or supervising authority to which it
        is subject.

- --------------------------------------------------------------------------------
                  Name                                        Address
- --------------------------------------------------------------------------------

    Superintendent of Banks of the State of  2 Rector Street, New York,
    New York                                 N.Y.  10006, and Albany, N.Y. 12203

    Federal Reserve Bank of New York         33 Liberty Plaza, New York,
                                             N.Y.  10045

    Federal Deposit Insurance Corporation    Washington, D.C.  20429

    New York Clearing House Association      New York, New York   10005

    (b) Whether it is authorized to exercise corporate trust powers.

    Yes.

2.  Affiliations with Obligor.

    If the obligor is an affiliate of the trustee, describe each such
    affiliation.

    None.

16. List of Exhibits.

    Exhibits identified in parentheses below, on file with the Commission, are
    incorporated herein by reference as an exhibit hereto, pursuant to Rule
    7a-29 under the Trust Indenture Act of 1939 (the "Act") and 17 C.F.R.
    229.10(d).

    1.  A copy of the Organization Certificate of The Bank of New York (formerly
        Irving Trust Company) as now in effect, which contains the authority to
        commence business and a grant of powers to exercise corporate trust
        powers. (Exhibit 1 to Amendment No. 1 to Form T-1 filed with
        Registration Statement No. 33-6215, Exhibits 1a and 1b to Form T-1 filed
        with Registration Statement No. 33-21672 and Exhibit 1 to Form T-1 filed
        with Registration Statement No. 33-29637.)

    4.  A copy of the existing By-laws of the Trustee. (Exhibit 4 to Form T-1
        filed with Registration Statement No. 33-31019.)


                                      -2-


    6.  The consent of the Trustee required by Section 321(b) of the Act.
        (Exhibit 6 to Form T-1 filed with Registration Statement No. 33-44051.)

    7.  A copy of the latest report of condition of the Trustee published
        pursuant to law or to the requirements of its supervising or examining
        authority.


                                      -3-


                                    SIGNATURE

    Pursuant to the requirements of the Act, the Trustee, The Bank of New York,
a corporation organized and existing under the laws of the State of New York,
has duly caused this statement of eligibility to be signed on its behalf by the
undersigned, thereunto duly authorized, all in The City of New York, and State
of New York, on the 19th day of June, 1997.

                                          THE BANK OF NEW YORK


                                          By:    /S/VIVIAN GEORGES
                                              ---------------------------------
                                              Name:  VIVIAN GEORGES
                                              Title: ASSISTANT VICE PRESIDENT


                                      -4-


THIS CONFORMING PAPER FORMAT DOCUMENT IS BEING SUBMITTED PURSUANT TO RULE 901(d)
OF REGULATION S-T

CONFORMED COPY

================================================================================

                                    FORM T-1

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                            STATEMENT OF ELIGIBILITY
                   UNDER THE TRUST INDENTURE ACT OF 1939 OF A
                    CORPORATION DESIGNATED TO ACT AS TRUSTEE

                      CHECK IF AN APPLICATION TO DETERMINE
                      ELIGIBILITY OF A TRUSTEE PURSUANT TO
                             SECTION 305(b)(2) |__|

                              --------------------

                              THE BANK OF NEW YORK
               (Exact name of trustee as specified in its charter)

New York                                                    13-5160382
(State of incorporation                                     (I.R.S. employer
if not a U.S. national bank)                                identification no.)

48 Wall Street, New York, N.Y.                              10286
(Address of principal executive offices)                    (Zip code)

                           -------------------------

                                 ONBANCORP, INC.
               (Exact name of obligor as specified in its charter)

Delaware
(State or other jurisdiction of                             (I.R.S. employer
incorporation or organization)                              identification no.)

101 South Salina Street
P.O. Box 4983
Syracuse, New York                                          13221-4983
(Address of principal executive offices)                    (Zip code)

                           -------------------------

               Junior Subordinated Deferrable Interest Debentures
                       (Title of the indenture securities)

================================================================================



1.  General information. Furnish the following information as to the Trustee:

    (a) Name and address of each examining or supervising authority to which it
        is subject.
 
- --------------------------------------------------------------------------------
                  Name                                        Address
- --------------------------------------------------------------------------------

    Superintendent of Banks of the State of  2 Rector Street, New York,
    New York                                 N.Y.  10006, and Albany, N.Y. 12203

    Federal Reserve Bank of New York         33 Liberty Plaza, New York,
                                             N.Y.  10045

    Federal Deposit Insurance Corporation    Washington, D.C.  20429

    New York Clearing House Association      New York, New York   10005

    (b) Whether it is authorized to exercise corporate trust powers.

    Yes.

2.  Affiliations with Obligor.
 
    If the obligor is an affiliate of the trustee, describe each such
    affiliation.

    None.

16. List of Exhibits.

    Exhibits identified in parentheses below, on file with the Commission, are
    incorporated herein by reference as an exhibit hereto, pursuant to Rule
    7a-29 under the Trust Indenture Act of 1939 (the "Act") and 17 C.F.R.
    229.10(d).

    1.  A copy of the Organization Certificate of The Bank of New York (formerly
        Irving Trust Company) as now in effect, which contains the authority to
        commence business and a grant of powers to exercise corporate trust
        powers. (Exhibit 1 to Amendment No. 1 to Form T-1 filed with
        Registration Statement No. 33-6215, Exhibits 1a and 1b to Form T-1 filed
        with Registration Statement No. 33-21672 and Exhibit 1 to Form T-1 filed
        with Registration Statement No. 33-29637.)

    4.  A copy of the existing By-laws of the Trustee. (Exhibit 4 to Form T-1
        filed with Registration Statement No. 33-31019.)


                                      -2-


    6.  The consent of the Trustee required by Section 321(b) of the Act.
        (Exhibit 6 to Form T-1 filed with Registration Statement No. 33-44051.)

    7.  A copy of the latest report of condition of the Trustee published
        pursuant to law or to the requirements of its supervising or examining
        authority.


                                      -3-


                                    SIGNATURE

    Pursuant to the requirements of the Act, the Trustee, The Bank of New York,
a corporation organized and existing under the laws of the State of New York,
has duly caused this statement of eligibility to be signed on its behalf by the
undersigned, thereunto duly authorized, all in The City of New York, and State
of New York, on the 19th day of June, 1997.

                                          THE BANK OF NEW YORK


                                          By:     /S/VIVIAN GEORGES   
                                             ----------------------------------
                                              Name:  VIVIAN GEORGES
                                              Title: ASSISTANT VICE PRESIDENT


                                      -4-



THIS CONFORMING PAPER FORMAT DOCUMENT IS BEING SUBMITTED PURSUANT TO RULE 901(d)
OF REGULATION S-T

================================================================================

                                    FORM T-1

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                            STATEMENT OF ELIGIBILITY
                   UNDER THE TRUST INDENTURE ACT OF 1939 OF A
                    CORPORATION DESIGNATED TO ACT AS TRUSTEE

                      CHECK IF AN APPLICATION TO DETERMINE
                      ELIGIBILITY OF A TRUSTEE PURSUANT TO
                             SECTION 305(b)(2) |__|

                            -------------------------

                              THE BANK OF NEW YORK
               (Exact name of trustee as specified in its charter)


New York                                                    13-5160382
(State of incorporation                                     (I.R.S. employer
if not a U.S. national bank)                                identification no.)

48 Wall Street, New York, N.Y.                              10286
(Address of principal executive offices)                    (Zip code)

                           -------------------------

                                 ONBANCORP, INC.
               (Exact name of obligor as specified in its charter)


Delaware
(State or other jurisdiction of                             (I.R.S. employer
incorporation or organization)                              identification no.)

101 South Salina Street
P.O. Box 4983
Syracuse, New York                                          13221-4983
(Address of principal executive offices)                    (Zip code)

                           -------------------------

                       Guarantee of Capital Securities of
                             OnBank Capital Trust I
                       (Title of the indenture securities)

================================================================================



1.  General information. Furnish the following information as to the Trustee:

    (a) Name and address of each examining or supervising authority to which it
        is subject.

- --------------------------------------------------------------------------------
                  Name                                        Address
- --------------------------------------------------------------------------------

    Superintendent of Banks of the State of  2 Rector Street, New York,
    New York                                 N.Y.  10006, and Albany, N.Y. 12203

    Federal Reserve Bank of New York         33 Liberty Plaza, New York,
                                             N.Y.  10045

    Federal Deposit Insurance Corporation    Washington, D.C.  20429

    New York Clearing House Association      New York, New York   10005

    (b) Whether it is authorized to exercise corporate trust powers.

    Yes.

2.  Affiliations with Obligor.

    If the obligor is an affiliate of the trustee, describe each such
affiliation.

    None.

16. List of Exhibits.

    Exhibits identified in parentheses below, on file with the Commission, are
    incorporated herein by reference as an exhibit hereto, pursuant to Rule
    7a-29 under the Trust Indenture Act of 1939 (the "Act") and 17 C.F.R.
    229.10(d).

    1.  A copy of the Organization Certificate of The Bank of New York (formerly
        Irving Trust Company) as now in effect, which contains the authority to
        commence business and a grant of powers to exercise corporate trust
        powers. (Exhibit 1 to Amendment No. 1 to Form T-1 filed with
        Registration Statement No. 33-6215, Exhibits 1a and 1b to Form T-1 filed
        with Registration Statement No. 33-21672 and Exhibit 1 to Form T-1 filed
        with Registration Statement No. 33-29637.)

    4.  A copy of the existing By-laws of the Trustee. (Exhibit 4 to Form T-1
        filed with Registration Statement No. 33-31019.)


                                       -2-


    6.  The consent of the Trustee required by Section 321(b) of the Act.
        (Exhibit 6 to Form T-1 filed with Registration Statement No. 33-44051.)

    7.  A copy of the latest report of condition of the Trustee published
        pursuant to law or to the requirements of its supervising or examining
        authority.


                                      -3-


                                    SIGNATURE

    Pursuant to the requirements of the Act, the Trustee, The Bank of New York,
a corporation organized and existing under the laws of the State of New York,
has duly caused this statement of eligibility to be signed on its behalf by the
undersigned, thereunto duly authorized, all in The City of New York, and State
of New York, on the 19th day of June, 1997.

                                          THE BANK OF NEW YORK


                                          By:     /S/VIVIAN GEORGES
                                              ---------------------------------
                                              Name:  VIVIAN GEORGES
                                              Title: ASSISTANT VICE PRESIDENT