[5] The Marion and Ralls County portions of Monroe City are part of the Hannibal Micropolitan Statistical Area.

[7] In 1907, Monroe City repealed its sundown town ordinance that it had set three weeks prior for Black people to return home by eight o'clock at night.

"[8] The Farmers and Merchants Bank Building, St. Jude's Episcopal Church, and Washington School are listed on the National Register of Historic Places.

Routes 24 and 36 split at Monroe City, with US 36 leading west-northwest 42 miles (68 km) to Macon and US 24 leading west-southwest 46 miles (74 km) to Moberly.

The two highways together lead east 22 miles (35 km) to Hannibal on the Mississippi River.

[12] As of the census[15] of 2010, there were 2,531 people, 1,036 households, and 623 families living in the city.

36.1% of all households were made up of individuals, and 17.2% had someone living alone who was 65 years of age or older.

As of the census[4] of 2000, there were 2,588 people, 1,061 households, and 661 families living in the city.

34.0% of all households were made up of individuals, and 15.8% had someone living alone who was 65 years of age or older.