24 cities
| City | County | 2025 Pop. ↓ |
|---|---|---|
| Fort Collins | Larimer County | 171,157 |
| Fountain | El Paso County | 29,349 |
| Four Square Mile | Arapahoe County | 26,775 |
| Firestone | Weld County | 20,079 |
| Fort Carson | El Paso County | 19,178 |
| Frederick | Weld County | 18,740 |
| Fruita | Mesa County | 14,034 |
| Federal Heights | Adams County | 13,865 |
| Fort Morgan | Morgan County | 11,905 |
| Fairmount | Adams County | 11,108 |
| Fort Lupton | Weld County | 10,433 |
| Fruitvale | Mesa County | 8,109 |
| Florence | Fremont County | 3,892 |
| Frisco | Summit County | 2,684 |
| Fraser | Grand County | 1,545 |
| Fowler | Otero County | 1,189 |
| Floyd Hill | Clear Creek County | 820 |
| Fairplay | Park County | 760 |
| Foxfield | Arapahoe County | 741 |
| Fort Garland | Costilla County | 619 |
| Flagler | Kit Carson County | 588 |
| Fleming | Logan County | 420 |
| Franktown | Douglas County | 340 |
| Florissant | Teller County | 190 |