Madison County is a county located in the U.S. state of Ohio. As of the most recent data available, the county has a population of approximately 40,213 people, with a population density of about 86.48 persons per square mile.
The county spans a total land area of 465.00 square miles (1,204.00 square kilometers). The administrative center and county seat is London, which often serves as a hub for local governance and services. The largest city within the county by population is London.
Geographically, Madison County experiences varied elevations, with its highest point at South Solon 1,118 ft and its lowest point at Choctaw Lake 0 ft. The region operates in the UTC-5.