Exhibit 23 Consent of Independent Certified Public Accountants The Board of Directors Ambanc Holding Co., Inc. We consent to incorporation by reference in the following registration statements: File No. 333-50973 on Form S-8, and File No. 333-50975 on Form S-8 of Ambanc Holding Co., Inc. of our report dated February 12, 1999, relating to the consolidated statements of financial condition of Ambanc Holding Co., Inc. and subsidiaries as of December 31, 1998 and 1997, and the related consolidated statements of operations, changes in shareholders' equity, and cash flows for each of the years in the three-year period ended December 31, 1998, which report appears in the December 31, 1998 Annual Report on Form 10-K of Ambanc Holding Co., Inc. /s/ KPMG LLP Albany, New York March 26, 1999