18 cities
| City | County | 2025 Pop. ↓ |
|---|---|---|
| Rifle | Garfield County | 10,651 |
| Roxborough Park | Douglas County | 9,046 |
| Redlands | Mesa County | 8,971 |
| Rocky Ford | Otero County | 3,786 |
| Rangely | Rio Blanco County | 2,276 |
| Ridgway | Ouray County | 1,291 |
| Rockvale | Fremont County | 546 |
| Red Feather Lakes | Larimer County | 449 |
| Redvale | Montrose County | 377 |
| Rico | Dolores County | 357 |
| Romeo | Conejos County | 312 |
| Red Cliff | Eagle County | 233 |
| Redstone | Eagle County | 220 |
| Rye | Pueblo County | 200 |
| Rollinsville | Gilpin County | 191 |
| Rock Creek Park | El Paso County | 176 |
| Raymer (New Raymer) | Morgan County | 111 |
| Ramah | El Paso County | 102 |