12 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Marble Hill | 1 | 1,381 | 1,381 | 0% | 835 | 2 | City |
| Marble Hill | 2 | 1,381 | 1,379 | 0% | 835 | 2 | City |
| Shakertowne | 3 | 565 | 545 | 7.21% | 428 | 1 | CDP |
| Sedgewickville | 4 | 189 | 188 | 0% | 295 | 1 | Village |
| Sedgewickville | 5 | 189 | 188 | 0% | 295 | 1 | Village |
| Longtown | 6 | 93 | 91 | 0% | 744 | 0 | Town |
| Longtown | 7 | 93 | 91 | 0% | 744 | 0 | Town |
| Zalma | 8 | 86 | 60 | 7.5% | 417 | 0 | CDP |
| Lithium | 9 | 59 | 88 | 7.27% | 77 | 1 | CDP |
| Glen Allen | 10 | 57 | 57 | 0% | 983 | 0 | Town |
| Glen Allen | 11 | 57 | 57 | 0% | 983 | 0 | Town |
| Biehle | 12 | 46 | 28 | 6.98% | 207 | 0 | CDP |
Marble Hill is the largest city in Bollinger County, with a population of 1,381.
Biehle is the smallest city in Bollinger County, with a population of 46.
There are 12 cities in Bollinger County, Missouri.