34 cities
| City | Rank | County | 2025 Pop. ↓ |
|---|---|---|---|
| Twin Falls | 1 | Twin Falls County | 56,457 |
| Jerome | 2 | Jerome County | 13,760 |
| Burley | 3 | Cassia County | 12,323 |
| Hailey | 4 | Blaine County | 10,169 |
| Rupert | 5 | Minidoka County | 6,413 |
| Kimberly | 6 | Twin Falls County | 5,826 |
| Buhl | 7 | Twin Falls County | 4,808 |
| Gooding | 8 | Gooding County | 3,851 |
| Heyburn | 9 | Minidoka County | 3,762 |
| Ketchum | 10 | Blaine County | 3,621 |
| Filer | 11 | Twin Falls County | 3,103 |
| Wendell | 12 | Gooding County | 3,058 |
| Bellevue | 13 | Blaine County | 2,586 |
| Paul | 14 | Minidoka County | 1,853 |
| Shoshone | 15 | Lincoln County | 1,781 |
| Sun Valley | 16 | Blaine County | 1,766 |
| Hansen | 17 | Twin Falls County | 1,124 |
| Hagerman | 18 | Gooding County | 995 |
| Oakley | 19 | Cassia County | 842 |
| Hazelton | 20 | Jerome County | 833 |
| Carey | 21 | Blaine County | 706 |
| Richfield | 22 | Lincoln County | 488 |
| Eden | 23 | Jerome County | 408 |
| Gannett | 24 | Blaine County | 395 |
| Declo | 25 | Cassia County | 369 |
| Dietrich | 26 | Lincoln County | 317 |
| Hollister | 27 | Jerome County | 273 |
| Bliss | 28 | Gooding County | 267 |
| Albion | 29 | Cassia County | 260 |
| Castleford | 30 | Twin Falls County | 229 |
| Malta | 31 | Cassia County | 181 |
| Acequia | 32 | Blaine County | 137 |
| Murtaugh | 33 | Twin Falls County | 125 |
| Minidoka | 34 | Minidoka County | 84 |
Twin Falls County, Jerome County, Cassia County, Blaine County, Minidoka County, Gooding County, and Lincoln County are the counties generally considered part of South Idaho.