[3] [4] McLeansboro is part of the Mount Vernon, Illinois micropolitan area.

[5] The city was named for Dr. William McLean, an early settler who had resided there in 1821.

[7] As of the 2020 census[3] there were 2,675 people, 1,114 households, and 661 families residing in the city.

There were 1,365 housing units at an average density of 474.95 per square mile (183.38/km2).

32.05% of all households were made up of individuals, and 23.97% had someone living alone who was 65 years of age or older.