23 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Greeley | 1 | 115,631 | 109,289 | 1.11% | 2,285 | 51 | City |
| Windsor | 2 | 43,857 | 33,241 | 5.09% | 1,667 | 26 | Town |
| Evans | 3 | 22,419 | 22,292 | 0.11% | 2,135 | 11 | City |
| Johnstown | 4 | 21,457 | 17,367 | 3.96% | 1,390 | 15 | Town |
| Firestone | 5 | 20,079 | 16,664 | 3.52% | 1,445 | 14 | Town |
| Frederick | 6 | 18,740 | 14,722 | 4.48% | 1,232 | 15 | Town |
| Severance | 7 | 12,442 | 8,001 | 7.69% | 965 | 13 | Town |
| Fort Lupton | 8 | 10,433 | 8,007 | 4.88% | 773 | 13 | City |
| Milliken | 9 | 9,264 | 8,451 | 1.78% | 709 | 13 | Town |
| Mead | 10 | 7,218 | 4,802 | 7.17% | 467 | 15 | Town |
| Dacono | 11 | 6,847 | 6,351 | 1.47% | 738 | 9 | City |
| Eaton | 12 | 5,836 | 5,851 | -0.05% | 1,847 | 3 | Town |
| Platteville | 13 | 2,890 | 2,960 | -0.48% | 860 | 3 | Town |
| Ault | 14 | 2,845 | 1,919 | 6.95% | 1,612 | 2 | Town |
| La Salle | 15 | 2,288 | 2,360 | -0.65% | 2,337 | 1 | Town |
| Keenesburg | 16 | 2,252 | 1,259 | 9.64% | 243 | 9 | Town |
| Hudson | 17 | 1,609 | 1,647 | -0.49% | 273 | 6 | Town |
| Kersey | 18 | 1,496 | 1,510 | -0.2% | 668 | 2 | Town |
| Pierce | 19 | 1,084 | 1,099 | -0.28% | 583 | 2 | Town |
| Gilcrest | 20 | 1,015 | 1,022 | -0.2% | 1,252 | 1 | Town |
| Nunn | 21 | 540 | 502 | 1.31% | 136 | 4 | Town |
| Garden City | 22 | 249 | 252 | -0.4% | 2,204 | 0 | Town |
| Grover | 23 | 151 | 156 | -0.66% | 254 | 1 | Town |
Greeley is the largest city in Weld County, with a population of 115,631.
Grover is the smallest city in Weld County, with a population of 151.
There are 23 cities in Weld County, Colorado.