Modesto is a village in Macoupin County, Illinois, United States. The population was 182 at the 2020 census, down from 252 in 2000. Modesto is located in northern Macoupin County at 39°28′37″N 89°58′58″W / 39.47694°N 89.98278°W. Illinois Route 111 passes through the village as Main Street, leading north 8 miles to Waverly and south 3 miles to Pa…Modesto is a village in Macoupin County, Illinois, United States. The population was 182 at the 2020 census, down from 252 in 2000. Modesto is located in northern Macoupin County at 39°28′37″N 89°58′58″W / 39.47694°N 89.98278°W. Illinois Route 111 passes through the village as Main Street, leading north 8 miles to Waverly and south 3 miles to Palmyra. Carlinville, the Macoupin county seat, is 19 miles to the southeast.