13 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Neoga township | 1 | 2,703 | 2,773 | -0.48% | 49 | 54.68 | Township |
| Greenup township | 2 | 2,204 | 2,264 | -0.5% | 46 | 47.45 | Township |
| Sumpter township | 3 | 1,969 | 2,020 | -0.46% | 43 | 45.69 | Township |
| Neoga | 4 | 1,361 | 1,396 | -0.51% | 979 | 1.39 | City |
| Greenup | 5 | 1,325 | 1,367 | -0.6% | 757 | 1.75 | Village |
| Spring Point township | 6 | 1,301 | 1,334 | -0.38% | 23 | 55.91 | Township |
| Toledo | 7 | 1,123 | 1,157 | -0.62% | 1,265 | 0.89 | Village |
| Woodbury township | 8 | 541 | 551 | -0.18% | 24 | 22.61 | Township |
| Cottonwood township | 9 | 473 | 484 | -0.42% | 14 | 32.73 | Township |
| Crooked Creek township | 10 | 362 | 369 | -0.28% | 11 | 34.16 | Township |
| Jewett | 11 | 195 | 197 | 0% | 194 | 1 | Village |
| Rose Hill | 12 | 85 | 85 | 0% | 134 | 0.63 | Village |
| Janesville | 13 | 55 | 38 | 7.84% | 902 | 0.06 | CDP |
Neoga township is the largest city in Cumberland County, with a population of 2,703.
Janesville is the smallest city in Cumberland County.
There are 13 cities in Cumberland County, Illinois.