EXHIBIT 23.6

CONSENT OF SANDLER O’NEILL & PARTNERS, L.P.

We hereby consent to the inclusion of our opinion letter, dated December 23, 2003, to the Board of Directors of Partners Trust Financial Group, Inc., a federal corporation, as an Appendix to the Joint Proxy Statement/Prospectus relating to the proposed merger of BSB Bancorp, Inc. into Partners Trust Financial Group, Inc., a Delaware corporation (“New Partners Trust”) contained in New Partners Trust’s Registration Statement on Form S-4 as filed with the Securities and Exchange Commission on the date hereof, and to the references to our firm and such opinion in such Joint Proxy Statement/Prospectus. In giving such consent, we do not admit that we come within the category of persons whose consent is required under Section 7 of the Securities Act of 1933, as amended (the “Act”), or the rules and regulations of the Securities and Exchange Commission thereunder (the “Regulations”), nor do we admit that we are experts with respect to any part of such Registration Statement within the meaning of the term “experts” as used in the Act or the Regulations.

/s/    Sandler O’Neill & Partners, L.P.

February 27, 2004