| City | County | 2026 Pop. ↓ |
|---|---|---|
| Caldwell | Canyon County | 79,746 |
| Coeur d'Alene | Kootenai County | 58,785 |
| Chubbuck | Bannock County | 17,049 |
| Cascade | Valley County | 1,024 |
| Council | Adams County | 1,009 |
| Challis | Custer County | 969 |
| Cottonwood | Idaho County | 944 |
| Carey | Blaine County | 732 |
| Clark Fork | Bonner County | 592 |
| Clifton | Franklin County | 476 |
| Craigmont | Lewis County | 472 |
| Culdesac | Nez Perce County | 418 |
| Cambridge | Washington County | 360 |
| Castleford | Twin Falls County | 233 |
| Crouch | Boise County | 185 |
| Conkling Park | Kootenai County | 161 |
| Coolin | Bonner County | 30 |
| Clayton | Custer County | 11 |