| City | Rank | County | 2026 Pop. ↓ |
|---|---|---|---|
| Rexburg | 1 | Madison County | 40,465 |
| St. Anthony | 2 | Fremont County | 4,081 |
| Victor | 3 | Teton County | 2,664 |
| Sugar City | 4 | Madison County | 2,631 |
| Driggs | 5 | Teton County | 2,485 |
| Ashton | 6 | Fremont County | 977 |
| Teton | 7 | Fremont County | 846 |
| Dubois | 8 | Clark County | 514 |
| Newdale | 9 | Fremont County | 328 |
| Parker | 10 | Fremont County | 288 |
| Tetonia | 11 | Teton County | 266 |
| Island Park | 12 | Fremont County | 189 |
| Spencer | 13 | Clark County | 28 |
| Drummond | 14 | Fremont County | 15 |
| Warm River | 15 | Fremont County | 1 |
Madison County, Fremont County, Teton County, and Clark County are the counties generally considered part of East Idaho.