11 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Sidney | 1 | 1,025 | 1,060 | -0.68% | 748 | 1.37 | City |
| Tabor | 2 | 967 | 1,009 | -0.82% | 748 | 1.29 | City |
| Hamburg | 3 | 854 | 888 | -0.81% | 761 | 1.12 | City |
| Farragut | 4 | 472 | 486 | -0.63% | 1,177 | 0.40 | City |
| Riverton | 5 | 237 | 247 | -0.84% | 393 | 0.60 | City |
| Randolph | 6 | 177 | 187 | -1.12% | 590 | 0.30 | City |
| Thurman | 7 | 162 | 164 | 0% | 287 | 0.56 | City |
| Percival | 8 | 130 | 73 | 7.44% | 295 | 0.44 | CDP |
| Anderson | 9 | 54 | 45 | 8% | 164 | 0.33 | CDP |
| Imogene | 10 | 37 | 39 | 0% | 75 | 0.49 | City |
| Bartlett | 11 | 15 | 8 | 7.14% | 38 | 0.40 | CDP |
Sidney is the largest city in Fremont County, with a population of 1,025.
Bartlett is the smallest city in Fremont County.
There are 11 cities in Fremont County, Iowa.