11 cities
| City | County | 2025 Pop. ↓ |
|---|---|---|
| Ammon | Bonneville County | 20,649 |
| American Falls | Power County | 4,937 |
| Aberdeen | Bingham County | 1,879 |
| Avimor | Ada County | 1,642 |
| Ashton | Fremont County | 982 |
| Arco | Butte County | 919 |
| Arbon Valley | Bannock County | 830 |
| Athol | Kootenai County | 745 |
| Arimo | Bannock County | 365 |
| Albion | Cassia County | 260 |
| Acequia | Blaine County | 137 |