All counties in Colorado
| County Name | Population | State | Rank |
|---|
| El Paso County | 622,263 | Colorado | 1 |
| Denver County | 600,158 | Colorado | 2 |
| Arapahoe County | 572,003 | Colorado | 3 |
| Jefferson County | 534,543 | Colorado | 4 |
| Adams County | 441,603 | Colorado | 5 |
| Larimer County | 299,630 | Colorado | 6 |
| Boulder County | 294,567 | Colorado | 7 |
| Douglas County | 285,465 | Colorado | 8 |
| Weld County | 252,825 | Colorado | 9 |
| Pueblo County | 159,063 | Colorado | 10 |
| Mesa County | 146,723 | Colorado | 11 |
| Garfield County | 56,389 | Colorado | 12 |
| Broomfield County | 55,889 | Colorado | 13 |
| Eagle County | 52,197 | Colorado | 14 |
| La Plata County | 51,334 | Colorado | 15 |
| Fremont County | 46,824 | Colorado | 16 |
| Montrose County | 41,276 | Colorado | 17 |
| Delta County | 30,952 | Colorado | 18 |
| Morgan County | 28,159 | Colorado | 19 |
| Summit County | 27,994 | Colorado | 20 |
| Montezuma County | 25,535 | Colorado | 21 |
| Routt County | 23,509 | Colorado | 22 |
| Teller County | 23,350 | Colorado | 23 |
| Elbert County | 23,086 | Colorado | 24 |
| Logan County | 22,709 | Colorado | 25 |
| Otero County | 18,831 | Colorado | 26 |
| Chaffee County | 17,809 | Colorado | 27 |
| Pitkin County | 17,148 | Colorado | 28 |
| Park County | 16,206 | Colorado | 29 |
| Las Animas County | 15,507 | Colorado | 30 |
| Alamosa County | 15,445 | Colorado | 31 |
| Gunnison County | 15,324 | Colorado | 32 |
| Grand County | 14,843 | Colorado | 33 |
| Moffat County | 13,795 | Colorado | 34 |
| Prowers County | 12,551 | Colorado | 35 |
| Archuleta County | 12,084 | Colorado | 36 |
| Rio Grande County | 11,982 | Colorado | 37 |
| Yuma County | 10,043 | Colorado | 38 |
| Clear Creek County | 9,088 | Colorado | 39 |
| Kit Carson County | 8,270 | Colorado | 40 |
| Conejos County | 8,256 | Colorado | 41 |
| San Miguel County | 7,359 | Colorado | 42 |
| Lake County | 7,310 | Colorado | 43 |
| Huerfano County | 6,711 | Colorado | 44 |
| Rio Blanco County | 6,666 | Colorado | 45 |
| Bent County | 6,499 | Colorado | 46 |
| Saguache County | 6,108 | Colorado | 47 |
| Crowley County | 5,823 | Colorado | 48 |
| Lincoln County | 5,467 | Colorado | 49 |
| Gilpin County | 5,441 | Colorado | 50 |
| Washington County | 4,814 | Colorado | 51 |
| Phillips County | 4,442 | Colorado | 52 |
| Ouray County | 4,436 | Colorado | 53 |
| Custer County | 4,255 | Colorado | 54 |
| Baca County | 3,788 | Colorado | 55 |
| Costilla County | 3,524 | Colorado | 56 |
| Sedgwick County | 2,379 | Colorado | 57 |
| Dolores County | 2,064 | Colorado | 58 |
| Cheyenne County | 1,836 | Colorado | 59 |
| Kiowa County | 1,398 | Colorado | 60 |
| Jackson County | 1,394 | Colorado | 61 |
| Hinsdale County | 843 | Colorado | 62 |
| Mineral County | 712 | Colorado | 63 |
| San Juan County | 699 | Colorado | 64 |