Stephenson is a city in Menominee County in the U.S. state of Michigan. The population was 816 at the 2020 census. The city is surrounded b…Stephenson is a city in Menominee County in the U.S. state of Michigan. The population was 816 at the 2020 census. The city is surrounded by Stephenson Township but is administered autonomously. It is part of the Marinette, WI–MI micropolitan statistical area.