United States--postal Service, Grantham 1 S College Ave Mechanicsburg, PA 17050 Phone : (717) 766-0953 Business Category Government Offices-Federal Government Offices & Public Schools Post Office - Grantham 1 S College Ave Grantham, PA 17027 Phone : (717) 766-0953 Business Category Post Offices Toll-Free           (800) ASK-USPS Fax           (717) 691-8464 United States Government--postal Service, Main Office, Nearby Offices, Grantham College Ave Grantham, PA 17027 Phone : (717) 766-0953 Business Category Government Offices-Federal Government Offices & Public Schools