Counties in Colorado by population, 2025

El Paso County had the highest population of 64 counties in 2025, at 757,040. Hinsdale County had the lowest, at 753. The median was 15,444 and the figure for Colorado was 6.01 million. Source: the U.S. Census Bureau.

Highest757,040El Paso County
Median15,44464 counties
Colorado6,012,561History

Top 40 counties, 2025

CSVChart (SVG)

El Paso CountyEl Paso County: 757,040 persons757,040Denver CountyDenver County: 740,613 persons740,613Arapahoe CountyArapahoe County: 673,820 persons673,820Jefferson CountyJefferson County: 580,451 persons580,451Adams CountyAdams County: 554,668 persons554,668Douglas CountyDouglas County: 399,396 persons399,396Weld CountyWeld County: 378,426 persons378,426Larimer CountyLarimer County: 377,292 persons377,292Boulder CountyBoulder County: 328,560 persons328,560Pueblo CountyPueblo County: 169,277 persons169,277Mesa CountyMesa County: 162,845 persons162,845Broomfield CountyBroomfield County: 79,174 persons79,174Garfield CountyGarfield County: 63,474 persons63,474La Plata CountyLa Plata County: 56,898 persons56,898Eagle CountyEagle County: 54,291 persons54,291Fremont CountyFremont County: 50,039 persons50,039Montrose CountyMontrose County: 44,591 persons44,591Delta CountyDelta County: 32,178 persons32,178Summit CountySummit County: 31,517 persons31,517Elbert CountyElbert County: 30,534 persons30,534Morgan CountyMorgan County: 30,306 persons30,306Montezuma CountyMontezuma County: 26,678 persons26,678Routt CountyRoutt County: 25,329 persons25,329Teller CountyTeller County: 24,756 persons24,756Chaffee CountyChaffee County: 20,831 persons20,831Logan CountyLogan County: 20,654 persons20,654Park CountyPark County: 18,314 persons18,314Otero CountyOtero County: 17,683 persons17,683Gunnison CountyGunnison County: 17,439 persons17,439Alamosa CountyAlamosa County: 16,688 persons16,688Pitkin CountyPitkin County: 16,625 persons16,625Grand CountyGrand County: 16,496 persons16,496Las Animas CountyLas Animas County: 14,391 persons14,391Archuleta CountyArchuleta County: 14,306 persons14,306Moffat CountyMoffat County: 13,122 persons13,122Prowers CountyProwers County: 11,884 persons11,884Rio Grande CountyRio Grande County: 11,087 persons11,087Yuma CountyYuma County: 9,896 persons9,896Clear Creek CountyClear Creek County: 8,994 persons8,994San Miguel CountySan Miguel County: 7,753 persons7,753
persons. Source: U.S. Census Bureau. Retrieved 2026-10-08.

Full ranking

RankCounties2025
persons
Change on 2024
1El Paso County757,040+0.6%
2Denver County740,613-0.1%
3Arapahoe County673,820-0.3%
4Jefferson County580,4510%
5Adams County554,668+1%
6Douglas County399,396+1.6%
7Weld County378,426+1.9%
8Larimer County377,292+0.8%
9Boulder County328,560-0.3%
10Pueblo County169,277-0.5%
11Mesa County162,845+0.9%
12Broomfield County79,174+1%
13Garfield County63,474-0.5%
14La Plata County56,898-0.1%
15Eagle County54,291-0.6%
16Fremont County50,039+0.1%
17Montrose County44,591-0.2%
18Delta County32,178-0.4%
19Summit County31,517-0.4%
20Elbert County30,534+4.1%
21Morgan County30,306-0%
22Montezuma County26,678-0.1%
23Routt County25,329-0.6%
24Teller County24,756+0.1%
25Chaffee County20,831+0.2%
26Logan County20,654-0.2%
27Park County18,314-0.2%
28Otero County17,683-1.1%
29Gunnison County17,439+0.2%
30Alamosa County16,688-0%
31Pitkin County16,625-0.8%
32Grand County16,496+1.3%
33Las Animas County14,391-0.8%
34Archuleta County14,306+1.2%
35Moffat County13,122-1.4%
36Prowers County11,884-0.2%
37Rio Grande County11,087-0.5%
38Yuma County9,896+0.2%
39Clear Creek County8,994-0.3%
40San Miguel County7,753-0.8%
41Lake County7,552+1.1%
42Conejos County7,529+0.1%
43Kit Carson County7,069+0.6%
44Huerfano County7,011+0.3%
45Saguache County6,732+0.7%
46Rio Blanco County6,683-1.6%
47Gilpin County6,073+2%
48Bent County5,716-0.5%
49Crowley County5,677+0.5%
50Lincoln County5,645+0.8%
51Custer County5,590+0.4%
52Ouray County5,265+1.8%
53Washington County4,732-0.3%
54Phillips County4,420-0.8%
55Costilla County3,679+0.2%
56Baca County3,347-1.2%
57Dolores County2,466+0.6%
58Sedgwick County2,247-1.1%
59Cheyenne County1,713+1.2%
60Kiowa County1,412+0.6%
61Jackson County1,211-5.2%
62Mineral County910-1.5%
63San Juan County813-1%
64Hinsdale County7530%

Other periods

About this ranking

Resident population. Spain and the EU: 1 January, with Spanish figures from the official municipal register (PadrĂ³n). United States: Census Bureau population estimates for 1 July. Other countries and the World: World Bank mid-year estimates, which count all residents regardless of legal status or citizenship.

For Denmark, Statistics Denmark counts the registered resident population on 1 January. Greenland and the Faroe Islands are excluded. The annual series selects the first-quarter reference date from FOLK1A. The World Bank series exists for every country, so use it (through compare) to rank countries on one basis.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. Equal values share a rank.

How to cite

U.S. Census Bureau. Annual estimates of the resident population for the United States, states and counties, 1 July (Population Estimates Program). https://www2.census.gov/programs-surveys/popest/datasets/2020-2025/. Retrieved 2026-10-08.

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Questions

Which county has the highest population?

El Paso County, with 757,040 in 2025, according to the U.S. Census Bureau.

Which county has the lowest population?

Hinsdale County, with 753 in 2025.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Census Bureau, Annual estimates of the resident population for the United States, states and counties, 1 July (Population Estimates Program). Retrieved 2026-10-08.

Population: other rankings

Counties in Colorado: more rankings