The Old Post Office and Courthouse is located at 157 Genessee Street in Auburn, New York. It was built in 1888–1890 and was designed by the Office of the Supervising Architect of the Treasury Department, Mifflin E. Bell, in the Richardsonian Romanesque style. It was expanded in 1913–1914, designed by James M. Elliot, and again in 1937. It serves as a courthouse of the United States District Court for the Northern District of New York. The building was surplussed by the Federal government in the 1980s and acquired by Cayuga County.