United States Postal Service Masachusetts Post Offices1-800-275-8777US Postal Service - Post Offices 800-275-8777Locate the local Post office in the area, print shipping labels and postage all online.Zip Codes.org United States Zip Code SearchEssex Post Office 4 Martin St.Essex, MA 01929978-768-0097Gloucester Post Office 15 Dale Ave.Gloucester, MA 01930978-283-2361Lanesville - Gloucester Post Office 1068 Washington StreetGloucester, MA 01930978-283-6998Magnolia - Gloucester Post Office 6 Lexington St.Gloucester, MA 01930978-525-3488Riverdale - Gloucester Post Office 3 Holly StreetGloucester, MA 01930978-283-6920Manchester Post Office 15 Beach St.Manchester, MA 01944978-526-4357