RANKING · 2025 ESTIMATES · 64 SHOWN OF 64

Fastest growing, Colorado counties

Colorado counties ranked by population growth from the 2020 census to 2025. This list covers the 64 counties in Colorado that qualify, ranked against each other statewide.

Flip the list · Fastest shrinking, US counties →

ColoradoAll states All rankings

SAME RANKING BYCities States Metros

RELATEDLargest by population Fastest shrinking Most population gained Most population lost Most densely populated Most sparsely populated

YEAR2000 2010 2020 2025

RANKPLACESTATEPOPPOPULATION GROWTHVS 2000

01Custer County, COCO5,590+18.8%−77%

02Elbert County, COCO30,534+17.2%−84%

03San Juan County, COCO813+15.3%−161%

04Weld County, COCO378,426+15.0%−60%

05Douglas County, COCO399,396+11.6%−94%

06Ouray County, COCO5,265+8.0%−87%

07Archuleta County, COCO14,306+7.1%−92%

08Chaffee County, COCO20,831+7.0%−75%

09Broomfield County, COCO79,174+6.8%–

10Adams County, COCO554,668+6.8%−82%

11Dolores County, COCO2,466+6.0%−73%

12Saguache County, COCO6,732+5.7%−80%

13Park County, COCO18,314+5.3%−95%

14Mineral County, COCO910+5.2%−89%

15Costilla County, COCO3,679+5.1%−65%

16Larimer County, COCO377,292+5.1%−86%

17Grand County, COCO16,496+5.0%−91%

18Mesa County, COCO162,845+4.6%−82%

19Gilpin County, COCO6,073+4.6%−92%

20Montrose County, COCO44,591+4.5%−88%

21Morgan County, COCO30,306+4.1%−83%

22El Paso County, COCO757,040+3.6%−88%

23Denver County, COCO740,613+3.5%−81%

24Montezuma County, COCO26,678+3.2%−88%

25Delta County, COCO32,178+3.1%−90%

26Gunnison County, COCO17,439+3.1%−91%

27Garfield County, COCO63,474+2.9%−94%

28Arapahoe County, COCO673,820+2.9%−88%

29Huerfano County, COCO7,011+2.8%−91%

30Rio Blanco County, COCO6,683+2.4%+906%

31La Plata County, COCO56,898+2.3%−94%

32Fremont County, COCO50,039+2.2%−95%

33Routt County, COCO25,329+2.0%−95%

34Alamosa County, COCO16,688+1.9%−81%

35Lake County, COCO7,552+1.6%−95%

36Summit County, COCO31,517+1.5%−98%

37Bent County, COCO5,716+1.2%−94%

38Conejos County, COCO7,529+0.9%−93%

39Pueblo County, COCO169,277+0.7%−96%

40Teller County, COCO24,756+0.2%−100%

41Kit Carson County, COCO7,069-0.3%−102%

42Jefferson County, COCO580,451-0.4%−102%

43Lincoln County, COCO5,645-0.5%−102%

44Boulder County, COCO328,560-0.7%−102%

45Yuma County, COCO9,896-0.9%−109%

46Prowers County, COCO11,884-1.0%−111%

47Las Animas County, COCO14,391-1.1%−111%

48Moffat County, COCO13,122-1.3%−108%

49Washington County, COCO4,732-1.8%−174%

50Cheyenne County, COCO1,713-2.0%−71%

51Kiowa County, COCO1,412-2.4%−40%

52Phillips County, COCO4,420-2.4%−135%

53Eagle County, COCO54,291-2.6%−103%

54Rio Grande County, COCO11,087-3.9%−126%

55San Miguel County, COCO7,753-4.0%−105%

56Logan County, COCO20,654-4.1%−124%

57Crowley County, COCO5,677-4.1%−110%

58Pitkin County, COCO16,625-4.2%−124%

59Clear Creek County, COCO8,994-4.3%−119%

60Hinsdale County, COCO753-4.4%−106%

61Baca County, COCO3,347-4.5%+430%

62Otero County, COCO17,683-5.4%−963%

63Sedgwick County, COCO2,247-6.5%−408%

64Jackson County, COCO1,211-12.2%+598%

SHOWING 1–64 OF 64

Download CSV (full list, 64 rows)

UPDATED 2026-07-15 · DATA: US CENSUS BUREAU POPULATION ESTIMATES