Identifiers: city · town · CDP
| Rank | Community | Population |
|---|---|---|
| 1 | Denver (city), CO | 715,522 |
| 2 | Thornton (city), CO | 141,867 |
| 3 | Arvada (city), CO | 124,402 |
| 4 | Westminster (city), CO | 116,317 |
| 5 | Boulder (city), CO | 108,250 |
| 6 | Longmont (city), CO | 98,885 |
| 7 | Broomfield (city), CO | 74,112 |
| 8 | Commerce City (city), CO | 62,418 |
| 9 | Brighton (city), CO | 40,083 |
| 10 | Northglenn (city), CO | 38,131 |
| 11 | Wheat Ridge (city), CO | 32,398 |
| 12 | Lafayette (city), CO | 30,411 |
| 13 | Erie (town), CO | 30,038 |
| 14 | Louisville (city), CO | 21,226 |
| 15 | Golden (city), CO | 20,399 |
| 16 | Sherrelwood (CDP), CO | 19,228 |
| 17 | Firestone (town), CO | 16,381 |
| 18 | Welby (CDP), CO | 15,553 |
| 19 | Frederick (town), CO | 14,513 |
| 20 | Federal Heights (city), CO | 14,382 |