St. Joseph (informally
St. Joe) is a city in and the
county seat of
Buchanan County,
Missouri,
United States. It is the principal city of the
St. Joseph Metropolitan Statistical Area, which includes Buchanan,
Andrew, and
DeKalb counties in Missouri and
Doniphan County,
Kansas. As of the
2010 census, St. Joseph had a total population of 76,780, making it the eighth largest city in the state, third largest in Northwest Missouri. The metropolitan area had a population of 127,329 in 2010.