11 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Farmington | 1 | 18,775 | 17,742 | 1.11% | 1,978 | 9.49 | City |
| Park Hills | 2 | 8,864 | 8,601 | 0.6% | 436 | 20.34 | City |
| Bonne Terre | 3 | 6,294 | 6,864 | -1.78% | 1,547 | 4.07 | City |
| Desloge | 4 | 4,897 | 4,826 | 0.29% | 1,678 | 2.92 | City |
| Bismarck | 5 | 1,240 | 1,240 | 0% | 1,245 | 1 | City |
| Leadwood | 6 | 1,161 | 1,175 | -0.26% | 1,003 | 1.16 | City |
| Leadington | 7 | 767 | 766 | 0% | 841 | 0.91 | City |
| Doe Run | 8 | 759 | 657 | -1.3% | 315 | 2.41 | CDP |
| Frankclay | 9 | 100 | 174 | -7.41% | 158 | 0.63 | CDP |
| Wortham | 10 | 96 | 429 | -11.11% | 108 | 0.89 | CDP |
| Knob Lick | 11 | 24 | 24 | 9.09% | 24 | 0.99 | CDP |
Farmington is the largest city in St. Francois County, with a population of 18,775.
Knob Lick is the smallest city in St. Francois County.
There are 11 cities in St. Francois County, Missouri.