| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Grangeville | 1 | 3,692 | 3,325 | 1.96% | 2,452 | 2 | City |
| Cottonwood | 2 | 944 | 820 | 2.5% | 1,125 | 1 | City |
| Kooskia | 3 | 559 | 512 | 1.64% | 909 | 1 | City |
| Riggins | 4 | 402 | 369 | 1.52% | 1,010 | 0 | City |
| Stites | 5 | 187 | 170 | 1.63% | 2,011 | 0 | City |
| Ferdinand | 6 | 143 | 131 | 1.42% | 817 | 0 | City |
| White Bird | 7 | 84 | 77 | 1.2% | 1,292 | 0 | City |
Grangeville is the largest city in Idaho County, with a population of 3,692.
White Bird is the smallest city in Idaho County, with a population of 84.
There are 7 cities in Idaho County, Idaho.