18 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Farmington | 1 | 19,520 | 18,219 | 1.85% | 2,056 | 9 | City |
| Farmington | 2 | 19,520 | 17,745 | 1.85% | 2,056 | 9 | City |
| Park Hills | 3 | 8,730 | 8,599 | 0.29% | 429 | 20 | City |
| Park Hills | 4 | 8,730 | 8,605 | 0.29% | 429 | 20 | City |
| Bonne Terre | 5 | 6,391 | 6,907 | -1.48% | 1,571 | 4 | City |
| Bonne Terre | 6 | 6,391 | 6,870 | -1.48% | 1,571 | 4 | City |
| Desloge | 7 | 4,838 | 4,820 | 0.04% | 1,658 | 3 | City |
| Desloge | 8 | 4,838 | 4,826 | 0.04% | 1,658 | 3 | City |
| Bismarck | 9 | 1,219 | 1,232 | -0.25% | 1,224 | 1 | City |
| Bismarck | 10 | 1,219 | 1,233 | -0.25% | 1,224 | 1 | City |
| Leadwood | 11 | 1,150 | 1,174 | -0.43% | 994 | 1 | City |
| Leadwood | 12 | 1,150 | 1,175 | -0.43% | 994 | 1 | City |
| Leadington | 13 | 762 | 765 | -0.13% | 836 | 1 | City |
| Leadington | 14 | 762 | 765 | -0.13% | 836 | 1 | City |
| Doe Run | 15 | 759 | 657 | -1.3% | 315 | 2 | CDP |
| Frankclay | 16 | 100 | 174 | -7.41% | 158 | 1 | CDP |
| Wortham | 17 | 96 | 429 | -11.11% | 108 | 1 | CDP |
| Knob Lick | 18 | 24 | 24 | 9.09% | 24 | 1 | CDP |
Farmington is the largest city in St. Francois County, with a population of 19,520.
Knob Lick is the smallest city in St. Francois County, with a population of 24.
There are 18 cities in St. Francois County, Missouri.