24 cities
| City | County | 2025 Pop. ↓ |
|---|---|---|
| Fort Collins | Larimer County | 170,638 |
| Fountain | El Paso County | 27,552 |
| Four Square Mile | Arapahoe County | 26,775 |
| Firestone | Weld County | 19,873 |
| Frederick | Weld County | 19,644 |
| Fort Carson | El Paso County | 19,178 |
| Fruita | Mesa County | 14,077 |
| Federal Heights | Adams County | 13,642 |
| Fort Morgan | Morgan County | 11,570 |
| Fairmount | Adams County | 11,108 |
| Fort Lupton | Weld County | 10,408 |
| Fruitvale | Mesa County | 8,109 |
| Florence | Fremont County | 3,876 |
| Frisco | Summit County | 2,655 |
| Fraser | Grand County | 1,493 |
| Fowler | Otero County | 1,181 |
| Floyd Hill | Clear Creek County | 820 |
| Fairplay | Park County | 742 |
| Foxfield | Arapahoe County | 722 |
| Fort Garland | Costilla County | 619 |
| Flagler | Kit Carson County | 580 |
| Fleming | Logan County | 417 |
| Franktown | Douglas County | 340 |
| Florissant | Teller County | 190 |