Town Hall Address 24 N. Street W. Middlesex, PA 16159 United States- Mercer County Deed Registry (724) 662-3800 http://www.mercerassessor.com/ias-portal Monday ~ Friday 8:30 am - 4:30 pm 109 Courthouse Mercer, PA 16137 United States Tax Collector 724-528-3752 14 Chestnut St. West Middlesex, PA 16159 United States Fire District (724) 528-2060 3439 Hubbard Middlesex Road PA 16159 United States County Mercer