County Census Records
Colorado Counties
65 counties with population data from the decennial US Census, 1790 to 2020.
65 counties
Population as of 2020 census
Adams
519,572
Alamosa
16,376
Arapahoe
655,070
Archuleta
13,359
Baca
3,506
Bent
5,650
Boulder
330,758
Broomfield
74,112
Chaffee
19,476
Cheyenne
1,748
Clear Creek
9,397
Conejos
7,461
Costilla
3,499
Crowley
5,922
Custer
4,704
Delta
31,196
Denver
715,522
Dolores
2,326
Douglas
357,978
Eagle
55,731
El Paso
730,395
Elbert
26,062
Fremont
48,939
Garfield
61,685
Gilpin
5,808
Grand
15,717
Greenwood
510
Gunnison
16,918
Hinsdale
788
Huerfano
6,820
Jackson
1,379
Jefferson
582,910
Kiowa
1,446
Kit Carson
7,087
La Plata
55,638
Lake
7,436
Larimer
359,066
Las Animas
14,555
Lincoln
5,675
Logan
21,528
Mesa
155,703
Mineral
865
Moffat
13,292
Montezuma
25,849
Montrose
42,679
Morgan
29,111
Otero
18,690
Ouray
4,874
Park
17,390
Phillips
4,530
Pitkin
17,358
Prowers
11,999
Pueblo
168,162
Rio Blanco
6,529
Rio Grande
11,539
Routt
24,829
Saguache
6,368
San Juan
705
San Miguel
8,072
Sedgwick
2,404
Summit
31,055
Teller
24,710
Washington
4,817
Weld
328,981
Yuma
9,988
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