7 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Hailey | 1 | 10,169 | 9,203 | 1.93% | 2,586 | 4 | City |
| Ketchum | 2 | 3,621 | 3,558 | 0.33% | 1,130 | 3 | City |
| Bellevue | 3 | 2,586 | 2,564 | 0.15% | 1,738 | 1 | City |
| Sun Valley | 4 | 1,766 | 1,790 | -0.28% | 185 | 10 | City |
| Carey | 5 | 706 | 690 | 0.43% | 205 | 3 | City |
| Gannett | 6 | 395 | 388 | 7.05% | 151 | 3 | CDP |
| Acequia | 7 | 137 | 130 | 0.74% | 257 | 1 | City |
Hailey is the largest city in Blaine County, with a population of 10,169.
Acequia is the smallest city in Blaine County, with a population of 137.
There are 7 cities in Blaine County, Idaho.