17 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Rock Springs | 1 | 22,835 | 23,495 | -0.57% | 1,156 | 20 | City |
| Green River | 2 | 11,390 | 11,808 | -0.73% | 825 | 14 | City |
| North Rock Springs | 3 | 2,610 | 2,727 | 1.05% | 177 | 15 | CDP |
| Purple Sage | 4 | 549 | 764 | 0.18% | 1,669 | 0 | CDP |
| James Town | 5 | 501 | 632 | -0.4% | 156 | 3 | CDP |
| Clearview Acres | 6 | 420 | 994 | -5.62% | 350 | 1 | CDP |
| Eden | 7 | 225 | 132 | -1.32% | 17 | 14 | CDP |
| Wamsutter | 8 | 195 | 202 | -1.02% | 120 | 2 | Town |
| Farson | 9 | 193 | 211 | -3.98% | 8 | 24 | CDP |
| Superior | 10 | 181 | 188 | -1.09% | 162 | 1 | Town |
| Granger | 11 | 97 | 96 | 0% | 37 | 3 | Town |
| McKinnon | 12 | 95 | 65 | 6.74% | 16 | 6 | CDP |
| Arrowhead Springs | 13 | 90 | 121 | 7.14% | 78 | 1 | CDP |
| Point Rocks | 14 | 85 | 58 | 7.59% | 39 | 2 | CDP |
| Bairoil | 15 | 65 | 68 | -1.52% | 46 | 1 | Town |
| Washam | 16 | 59 | 67 | 7.27% | 19 | 3 | CDP |
| Little America | 17 | 26 | 29 | 8.33% | 10 | 3 | CDP |
Rock Springs is the largest city in Sweetwater County, with a population of 22,835.
Little America is the smallest city in Sweetwater County, with a population of 26.
There are 17 cities in Sweetwater County, Wyoming.