the machias post office and customhouse is located at the western corner of center street and main street (united states route 1) in the heart of machias' downtown area. it is a two-story red brick building, topped by a hip roof and set on a granite foundation. its main facade faces main street, and is a symmetrical three bays wide, with the center bay projecting slightly and capped by a fully pedimented gable. one principal entrance is on the first floor of that section, set in a round-arch opening with keystone and pilastered columns. windows are set in round-arch openings on the first floor and segmented-arch openings on the second, with stone sills and keystones. the center street facade is five bays wide, with a similar arrangement and styling of doors and windows.