23 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Carrollton | 1 | 2,688 | 2,889 | -1.43% | 60 | 44 | Township |
| White Hall | 2 | 2,331 | 2,507 | -1.44% | 55 | 42 | Township |
| Carrollton | 3 | 2,322 | 2,478 | -1.11% | 1,221 | 2 | City |
| White Hall | 4 | 2,126 | 2,270 | -1.12% | 825 | 3 | City |
| Roodhouse | 5 | 1,731 | 1,863 | -1.37% | 44 | 40 | Township |
| Roodhouse | 6 | 1,464 | 1,569 | -1.15% | 1,299 | 1 | City |
| Rockbridge | 7 | 1,451 | 1,556 | -1.29% | 30 | 48 | Township |
| Greenfield | 8 | 1,006 | 989 | 0% | 58 | 17 | Township |
| Greenfield | 9 | 983 | 1,052 | -1.11% | 574 | 2 | City |
| Kane | 10 | 718 | 770 | -1.24% | 15 | 49 | Township |
| Bluffdale | 11 | 421 | 452 | -1.41% | 9 | 45 | Township |
| Patterson | 12 | 377 | 403 | -1.31% | 8 | 47 | Township |
| Linder | 13 | 295 | 319 | -1.34% | 9 | 35 | Township |
| Rubicon | 14 | 278 | 296 | -1.07% | 8 | 36 | Township |
| Kane | 15 | 273 | 294 | -1.09% | 502 | 1 | Village |
| Athensville | 16 | 257 | 283 | -2.28% | 7 | 36 | Township |
| Wrights | 17 | 208 | 225 | -1.42% | 6 | 36 | Township |
| Woodville | 18 | 196 | 208 | -1.01% | 4 | 48 | Township |
| Rockbridge | 19 | 168 | 179 | -1.18% | 228 | 1 | Village |
| Walkerville | 20 | 156 | 164 | -0.64% | 4 | 39 | Township |
| Eldred | 21 | 141 | 150 | -0.7% | 1,052 | 0 | Village |
| Hillview | 22 | 90 | 95 | -1.1% | 110 | 1 | Village |
| Otterville | 23 | 81 | 86 | -1.22% | 81 | 1 | Town |
Carrollton is the largest city in Greene County, with a population of 2,688.
Otterville is the smallest city in Greene County, with a population of 81.
There are 23 cities in Greene County, Illinois.