9 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Boone | 1 | 12,464 | 12,448 | 0.02% | 1,364 | 9 | City |
| Madrid | 2 | 2,830 | 2,800 | 0.21% | 2,312 | 1 | City |
| Ogden | 3 | 1,960 | 2,007 | -0.51% | 1,433 | 1 | City |
| Boxholm | 4 | 175 | 182 | -1.13% | 174 | 1 | City |
| Pilot Mound | 5 | 153 | 160 | -1.29% | 155 | 1 | City |
| Luther | 6 | 146 | 150 | -0.68% | 248 | 1 | City |
| Fraser | 7 | 107 | 105 | 0% | 94 | 1 | City |
| Beaver | 8 | 46 | 45 | 0% | 184 | 0 | City |
| Berkley | 9 | 22 | 24 | -4.35% | 109 | 0 | City |
Boone is the largest city in Boone County, with a population of 12,464.
Berkley is the smallest city in Boone County, with a population of 22.
There are 9 cities in Boone County, Iowa.