US Post Office-Herkimer is a historic post office building located at Herkimer in Herkimer County, New York, United States. It was designed and built in 1933-1934 by consulting architect Ross Edgar Sluyter for the Office of the Supervising Architect of the Treasury Department. It is a one-story, seven bay building faced with red brick laid in Flemish bond above a granite clad foundation in the Colonial Revival style. The five central bays are formed as a central pavilion and faced in terra cotta marked by Corinthian order pilasters. It was listed on the National Register of Historic Places in 1989.