McLeansboro is a city in Hamilton County, Illinois, United States. The population was 2,675 at the 2020 census.[1] It is the county seat of Hamilton County.[2] [1]"McLeansboro city, Illinois". United States Census Bureau. Retrieved September 20, 2023.[2]"Find a County". National Association of Counties. Archived from the original on May 31, 2011. Retrieved 2011-06-07. This short article about a place or feature in the United States can be made longer. You can help Wikipedia by adding to it.