23 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Carrollton | 1 | 2,727 | 2,889 | -1.41% | 61 | 44 | Township |
| White Hall | 2 | 2,365 | 2,507 | -1.42% | 56 | 42 | Township |
| Carrollton | 3 | 2,348 | 2,478 | -1.1% | 1,234 | 2 | City |
| White Hall | 4 | 2,150 | 2,270 | -1.1% | 834 | 3 | City |
| Roodhouse | 5 | 1,755 | 1,863 | -1.35% | 44 | 40 | Township |
| Roodhouse | 6 | 1,481 | 1,569 | -1.2% | 1,314 | 1 | City |
| Rockbridge | 7 | 1,470 | 1,556 | -1.28% | 31 | 48 | Township |
| Greenfield | 8 | 1,006 | 989 | 0% | 58 | 17 | Township |
| Greenfield | 9 | 994 | 1,052 | -1.19% | 580 | 2 | City |
| Kane | 10 | 727 | 770 | -1.22% | 15 | 49 | Township |
| Bluffdale | 11 | 427 | 452 | -1.39% | 10 | 45 | Township |
| Patterson | 12 | 382 | 403 | -1.29% | 8 | 47 | Township |
| Linder | 13 | 299 | 319 | -1.32% | 9 | 35 | Township |
| Rubicon | 14 | 281 | 296 | -1.06% | 8 | 36 | Township |
| Kane | 15 | 276 | 294 | -1.43% | 507 | 1 | Village |
| Athensville | 16 | 263 | 283 | -2.23% | 7 | 36 | Township |
| Wrights | 17 | 211 | 225 | -1.4% | 6 | 36 | Township |
| Woodville | 18 | 198 | 208 | -1% | 4 | 48 | Township |
| Rockbridge | 19 | 170 | 179 | -1.16% | 231 | 1 | Village |
| Walkerville | 20 | 157 | 164 | -0.63% | 4 | 39 | Township |
| Eldred | 21 | 142 | 150 | -1.39% | 1,060 | 0 | Village |
| Hillview | 22 | 91 | 95 | -1.09% | 112 | 1 | Village |
| Otterville | 23 | 82 | 86 | -1.2% | 82 | 1 | Town |
Carrollton is the largest city in Greene County, with a population of 2,727.
Otterville is the smallest city in Greene County, with a population of 82.
There are 23 cities in Greene County, Illinois.