7 cities
| City | County | 2026 Pop. ↓ |
|---|---|---|
| Johnstown | Weld County | 22,275 |
| Julesburg | Sedgwick County | 1,187 |
| Jamestown | Boulder County | 241 |
| Jackson Lake | Morgan County | 233 |
| Johnson Village | Chaffee County | 188 |
| Joes | Yuma County | 132 |
| Jansen | Las Animas County | 90 |