Bartelso is a village in Clinton County, Illinois, United States.

Carlyle, the Clinton County seat, is 8 miles (13 km) to the northeast.

According to the 2021 census gazetteer files, Bartelso has a total area of 0.43 square miles (1.11 km2), all land.

There were 244 housing units at an average density of 566.13 per square mile (218.58/km2).

24.92% of all households were made up of individuals, and 16.92% had someone living alone who was 65 years of age or older.