54 Pa.C.S. § 704.1

A surviving spouse may, at any time, resume any prior surname used by him or her by filing a written notice to such effect in the office of the prothonotary of the county where the surviving spouse resides, accompanied by a certificate of death for the decedent. In counties where there is no prothonotary, the notice shall be filed in the office that performs the functions of the office of prothonotary as provided for in the act of August 9, 1955 (P.L.323, No.130), known as The County Code.