Tax Assessment Cathy S. Herriott, Chief Assessor 4 Mercer County Courthouse Mercer, PA 16137 Telephone: (724) 662-7551 Fax Number: (724) 662-7549 Email: cherriott@mcc.co.mercer.pa.us Office Hours: Monday ~ Friday 8:30 am - 4:30 pm Except Holidays