| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Lincoln | 1 | 12,938 | 13,247 | -0.33% | 2,071 | 6 | City |
| Atlanta | 2 | 1,619 | 1,668 | -0.43% | 1,296 | 1 | City |
| Mount Pulaski | 3 | 1,493 | 1,532 | -0.4% | 1,317 | 1 | City |
| Emden | 4 | 449 | 465 | -0.66% | 1,911 | 0 | Village |
| Elkhart | 5 | 434 | 448 | -0.69% | 232 | 2 | Village |
| Latham | 6 | 319 | 330 | -0.62% | 1,168 | 0 | Village |
| Middletown | 7 | 316 | 323 | -0.32% | 927 | 0 | Village |
| New Holland | 8 | 260 | 269 | -0.76% | 839 | 0 | Village |
| Hartsburg | 9 | 253 | 261 | -0.78% | 1,687 | 0 | Village |
| Broadwell | 10 | 137 | 141 | -0.72% | 761 | 0 | Village |
Lincoln is the largest city in Logan County, with a population of 12,938.
Broadwell is the smallest city in Logan County, with a population of 137.
There are 10 cities in Logan County, Illinois.