[LETTERHEAD OF PRICE WATERHOUSE APPEARS HERE] EXHIBIT 23 CONSENT OF INDEPENDENT ACCOUNTANTS We hereby consent to the incorporation by reference in the Registration Statement on Form S-8 (No. 333-11443) of SIS Bancorp, Inc. of our report dated January 23, 1997 appearing on page 67 of this Form 10-K. /s/ Price Waterhouse LLP Boston, Massachusetts March 10, 1997