| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Rock Springs | 1 | 22,817 | 23,490 | -0.52% | 1,155 | 20 | City |
| Green River | 2 | 11,370 | 11,815 | -0.7% | 823 | 14 | City |
| Wamsutter | 3 | 195 | 202 | -1.02% | 120 | 2 | Town |
| Superior | 4 | 178 | 187 | -1.11% | 159 | 1 | Town |
| Granger | 5 | 97 | 94 | 0% | 37 | 3 | Town |
| Bairoil | 6 | 65 | 68 | -1.52% | 46 | 1 | Town |
Rock Springs is the largest city in Sweetwater County, with a population of 22,817.
Bairoil is the smallest city in Sweetwater County, with a population of 65.
There are 6 cities in Sweetwater County, Wyoming.