US Post Office-Hamilton is a historic post office building located at Hamilton in Madison County, New York, United States. It was designed and built in 1936, and is one of a number of post offices in New York State designed by the Office of the Supervising Architect of the Treasury Department, Louis A. Simon. It is a one-story, five bay steel frame building with a raised poured concrete foundation and brick watercourse in the Colonial Revival style. The interior features a 1938 relief sculpture by Humbert Albrizio titled "The Messengers." It was listed on the National Register of Historic Places in 1989.