The United States Post Office (also known as the Old Federal Building) at 209 East Portage Avenue in Sault Ste. Marie, Michigan, is an historic building which has served various purposes since its construction in the early 20th century. The building was listed on the National Register of Historic Places on September 9, 1977. The building was constructed in 1909-1910 of limestone from a Bedford, Indiana quarry. It served for decades as a post office and a courthouse of the United States District Court for the Western District of Michigan, with the court meeting there from 1912 until 1941.