Home/PostalMag/Post Office Photos/Barclay, Maryland Post Office Post Office Photos Barclay, Maryland Post Office PostalMag · Sunday, June 09, 2019 The Barclay, Maryland Post Office serves ZIP Code 21607. Photo by Jimmy Emerson, some rights reserved. Photo shared under the Creative Commons License. Barclay Post Office 1325 Goldsboro Rd Barclay, MD 21607