7 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Charleston | 1 | 17,252 | 17,579 | -0.31% | 1,901 | 9 | City |
| Mattoon | 2 | 16,476 | 16,853 | -0.38% | 1,597 | 10 | City |
| Oakland | 3 | 713 | 734 | -0.42% | 911 | 1 | City |
| Ashmore | 4 | 622 | 637 | -0.32% | 773 | 1 | Village |
| Humboldt | 5 | 354 | 360 | -0.28% | 1,032 | 0 | Village |
| Lerna | 6 | 216 | 221 | -0.46% | 1,878 | 0 | Village |
| Allenville | 7 | 129 | 132 | 0% | 212 | 1 | Village |
Charleston is the largest city in Coles County, with a population of 17,252.
Allenville is the smallest city in Coles County, with a population of 129.
There are 7 cities in Coles County, Illinois.