17 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Savanna | 1 | 3,310 | 3,405 | -0.51% | 248 | 13 | Township |
| York | 2 | 2,750 | 2,771 | -0.11% | 58 | 47 | Township |
| Savanna | 3 | 2,670 | 2,774 | -0.78% | 1,021 | 3 | City |
| Rock Creek-Lima | 4 | 1,928 | 1,980 | -0.41% | 36 | 54 | Township |
| Mount Carroll | 5 | 1,900 | 1,959 | -0.58% | 50 | 38 | Township |
| Thomson | 6 | 1,594 | 1,611 | -0.19% | 718 | 2 | Village |
| Cherry Grove-Shannon | 7 | 1,580 | 1,541 | -0.25% | 29 | 54 | Township |
| Lanark | 8 | 1,444 | 1,498 | -0.76% | 1,288 | 1 | City |
| Mount Carroll | 9 | 1,418 | 1,475 | -0.77% | 708 | 2 | City |
| Wysox | 10 | 1,297 | 1,335 | -0.54% | 34 | 38 | Township |
| Milledgeville | 11 | 988 | 1,023 | -0.7% | 1,432 | 1 | Village |
| Lake Carroll | 12 | 947 | 500 | 7.13% | 70 | 14 | CDP |
| Shannon | 13 | 880 | 800 | 1.85% | 1,826 | 0 | Village |
| Freedom | 14 | 773 | 780 | -0.13% | 22 | 36 | Township |
| Fairhaven | 15 | 759 | 767 | -0.13% | 20 | 38 | Township |
| Chadwick | 16 | 473 | 482 | -0.42% | 1,521 | 0 | Village |
| Elkhorn Grove | 17 | 189 | 189 | 0.53% | 10 | 20 | Township |
Savanna is the largest city in Carroll County, with a population of 3,310.
Elkhorn Grove is the smallest city in Carroll County, with a population of 189.
There are 17 cities in Carroll County, Illinois.