8 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| St. Anthony | 1 | 4,236 | 3,708 | 2.57% | 2,201 | 1.93 | City |
| Ashton | 2 | 951 | 950 | 0% | 1,491 | 0.64 | City |
| Teton | 3 | 872 | 791 | 1.87% | 1,266 | 0.69 | City |
| Newdale | 4 | 332 | 331 | 0% | 1,804 | 0.18 | City |
| Parker | 5 | 296 | 300 | -0.34% | 853 | 0.35 | City |
| Island Park | 6 | 192 | 194 | 0% | 32 | 6.08 | City |
| Drummond | 7 | 15 | 14 | 0% | 156 | 0.10 | City |
| Warm River | 8 | 0 | 0 | 0.00 | 0.67 | City |
St. Anthony is the largest city in Fremont County, with a population of 4,236.
Warm River is the smallest city in Fremont County.
There are 8 cities in Fremont County, Idaho.