4 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Marble Hill | 1 | 1,382 | 1,379 | 0.07% | 836 | 2 | City |
| Sedgewickville | 2 | 189 | 188 | 0% | 295 | 1 | Village |
| Longtown | 3 | 94 | 91 | 1.08% | 752 | 0 | Town |
| Glen Allen | 4 | 57 | 57 | 0% | 983 | 0 | Town |
Marble Hill is the largest city in Bollinger County, with a population of 1,382.
Glen Allen is the smallest city in Bollinger County, with a population of 57.
There are 4 cities in Bollinger County, Missouri.