13 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Dixon | 1 | 15,051 | 15,366 | -0.34% | 1,588 | 9 | City |
| Amboy | 2 | 2,198 | 2,276 | -0.59% | 365 | 6 | City |
| Ashton | 3 | 927 | 962 | -0.64% | 1,286 | 1 | Village |
| Franklin Grove | 4 | 865 | 898 | -0.57% | 2,079 | 0 | Village |
| Paw Paw | 5 | 795 | 827 | -0.63% | 1,327 | 1 | Village |
| Sublette | 6 | 368 | 379 | -0.54% | 920 | 0 | Village |
| Lee | 7 | 306 | 312 | -0.33% | 1,545 | 0 | Village |
| Compton | 8 | 264 | 270 | -0.38% | 1,600 | 0 | Village |
| Steward | 9 | 221 | 227 | -0.45% | 1,674 | 0 | Village |
| Coleta | 10 | 159 | 164 | -0.63% | 430 | 0 | Village |
| West Brooklyn | 11 | 126 | 131 | -0.79% | 1,340 | 0 | Village |
| Nelson | 12 | 123 | 128 | -0.81% | 345 | 0 | Village |
| Harmon | 13 | 116 | 119 | 0% | 532 | 0 | Village |
Dixon is the largest city in Lee County, with a population of 15,051.
Harmon is the smallest city in Lee County, with a population of 116.
There are 13 cities in Lee County, Illinois.