13 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Neoga | 1 | 2,759 | 2,775 | 0.44% | 50 | 55 | Township |
| Greenup | 2 | 2,240 | 2,263 | 0.27% | 47 | 47 | Township |
| Sumpter | 3 | 1,999 | 2,020 | 0.3% | 44 | 46 | Township |
| Neoga | 4 | 1,379 | 1,396 | -0.29% | 992 | 1 | City |
| Greenup | 5 | 1,342 | 1,367 | -0.37% | 767 | 2 | Village |
| Spring Point | 6 | 1,323 | 1,335 | 0.38% | 24 | 56 | Township |
| Toledo | 7 | 1,137 | 1,157 | -0.35% | 1,280 | 1 | Village |
| Woodbury | 8 | 546 | 552 | 0.18% | 24 | 23 | Township |
| Cottonwood | 9 | 478 | 483 | 0.42% | 15 | 33 | Township |
| Crooked Creek | 10 | 366 | 371 | 0.27% | 11 | 34 | Township |
| Jewett | 11 | 193 | 197 | -0.52% | 192 | 1 | Village |
| Rose Hill | 12 | 82 | 85 | -1.2% | 129 | 1 | Village |
| Janesville | 13 | 55 | 38 | 7.84% | 902 | 0 | CDP |
Neoga is the largest city in Cumberland County, with a population of 2,759.
Janesville is the smallest city in Cumberland County, with a population of 55.
There are 13 cities in Cumberland County, Illinois.