The smallest Post Office is located in Ochopee, FL (34141) and is 61.3 square feet. The building used to be a storage facility for irrigation pipes of an adjacent tomato farm. It was converted into a Post Office in 1953, after a fire that destroyed a previous Post Office and general store.
There is a sign beside the office that reads:
OCHOPEE POST OFFICE
Considered to be the smallest post office in the United States, this building was formerly an irrigation pipe shed belonging to the J.T. Gaunt Company tomato farm. It was hurriedly pressed into service by postmaster Sidney Brown after a disastrous night fire in 1953 burned Ochopee’s general store and post office. The present structure has been in continuous use ever since – as both a post office and ticket station for Trailway’s bus lines – and still services residents in a three-county area, including deliveries to Seminole and Miccosukee Indians living in the region. Daily business often includes requests from tourists and stamp collectors the world over for the famed Ochopee postmark. The property was acquired by the Wooten Family in 1992.
— Collier County Board of County Commissioners