RANKING · 2025 ESTIMATES · 99 SHOWN OF 99

Fastest growing, Iowa counties

Iowa counties ranked by population growth from the 2020 census to 2025. This list covers the 99 counties in Iowa that qualify, ranked against each other statewide. The median across all 99 is -1.1%. Biggest climber in the top 100 since 2020: Decatur County, IA, up 65 places to #33.

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SAME RANKING BYCities States Metros

YEAR2000 2010 2020 2025

RANKPLACESTATEPOPPOPULATION GROWTHVS 2000

01Dallas County, IAIA118,457+18.8%−18.1 pts

02▲2Warren County, IAIA57,331+9.4%−3.5 pts

03Polk County, IAIA516,546+4.9%−9.6 pts

04▼2Johnson County, IAIA160,044+4.7%−10.8 pts

05▲6Madison County, IAIA17,270+4.4%−7.9 pts

06▲19Wayne County, IAIA6,738+3.7%+8.5 pts

07▲9Lyon County, IAIA12,354+3.5%+5.1 pts

08▲22Jones County, IAIA21,253+2.9%−1.1 pts

09▼4Story County, IAIA101,291+2.8%−4.9 pts

10▼3Sioux County, IAIA36,774+2.5%−3.1 pts

11▲45Lucas County, IAIA8,847+2.5%−1.4 pts

12▲16Marion County, IAIA34,192+2.3%−4.5 pts

13▲56Mills County, IAIA14,793+2.1%−8.1 pts

14▼6Dickinson County, IAIA18,077+2.1%−8.0 pts

15▲32Benton County, IAIA26,004+1.7%−11.2 pts

16▲29Buchanan County, IAIA20,883+1.5%+0.4 pts

17▲40Guthrie County, IAIA10,782+1.5%−2.3 pts

18▼5Davis County, IAIA9,230+1.3%−1.4 pts

19▲27Allamakee County, IAIA14,238+1.3%−4.7 pts

20▼3Bremer County, IAIA25,296+1.2%−1.0 pts

21▲20Delaware County, IAIA17,674+1.1%−1.0 pts

22▼1Jasper County, IAIA38,153+0.9%−6.1 pts

23▲25Mitchell County, IAIA10,650+0.8%+1.3 pts

24▼18Linn County, IAIA232,028+0.8%−12.8 pts

25▼10Woodbury County, IAIA106,649+0.7%−5.0 pts

26▼12Washington County, IAIA22,667+0.5%−4.9 pts

27▼17Scott County, IAIA175,259+0.3%−4.8 pts

28▼4Boone County, IAIA26,799+0.3%−3.8 pts

29Black Hawk County, IAIA131,532+0.3%−3.1 pts

30▲22Harrison County, IAIA14,623+0.3%−6.1 pts

31▲9O'Brien County, IAIA14,220+0.3%+2.5 pts

32▲3Grundy County, IAIA12,361+0.3%−2.6 pts

33▲65Decatur County, IAIA7,655+0.1%−4.1 pts

34▼25Dubuque County, IAIA99,381+0.1%−3.1 pts

35▼17Plymouth County, IAIA25,697-0.0%−6.3 pts

36▲19Webster County, IAIA36,838-0.4%−0.2 pts

37▲60Ringgold County, IAIA4,642-0.5%−1.4 pts

38▲25Shelby County, IAIA11,689-0.5%−0.1 pts

39Marshall County, IAIA39,890-0.5%−3.2 pts

40▼4Howard County, IAIA9,415-0.6%−1.8 pts

41▲29Hamilton County, IAIA14,944-0.6%−2.9 pts

42▼9Wapello County, IAIA35,210-0.6%−1.7 pts

43▼16Pottawattamie County, IAIA92,996-0.7%−6.9 pts

44▼13Cedar County, IAIA18,359-0.8%−5.4 pts

45▼23Iowa County, IAIA16,504-0.9%−8.1 pts

46▲39Clinton County, IAIA46,002-1.0%+0.8 pts

47▲34Van Buren County, IAIA7,131-1.0%−2.7 pts

48▼4Jackson County, IAIA19,288-1.0%−2.7 pts

49▲43Taylor County, IAIA5,835-1.0%+1.2 pts

50▲24Palo Alto County, IAIA8,899-1.1%+3.8 pts

51▼1Wright County, IAIA12,801-1.1%−1.6 pts

52▼10Clay County, IAIA16,202-1.1%+0.1 pts

53▲34Clayton County, IAIA16,845-1.2%+0.8 pts

54Adair County, IAIA7,403-1.2%+0.7 pts

55▲44Fremont County, IAIA6,522-1.3%+1.4 pts

56▲30Cass County, IAIA12,960-1.3%+1.7 pts

57▲31Greene County, IAIA8,658-1.3%−4.5 pts

58▼24Mahaska County, IAIA21,880-1.4%−5.2 pts

59▼10Worth County, IAIA7,338-1.4%−0.4 pts

60▲29Franklin County, IAIA9,868-1.5%+4.3 pts

61▼23Poweshiek County, IAIA18,368-1.6%−0.4 pts

62▲16Winneshiek County, IAIA19,733-1.7%−3.9 pts

63▼3Crawford County, IAIA16,237-1.7%−2.7 pts

64▼11Cerro Gordo County, IAIA42,372-1.8%−1.1 pts

65▼53Clarke County, IAIA9,574-1.8%−12.0 pts

66▼47Buena Vista County, IAIA20,449-1.8%−4.0 pts

67▲6Appanoose County, IAIA12,077-1.9%−1.8 pts

68▼17Humboldt County, IAIA9,409-2.0%+1.5 pts

69▼4Tama County, IAIA16,796-2.0%−5.9 pts

70▼4Butler County, IAIA14,049-2.0%+0.7 pts

71▼7Des Moines County, IAIA38,077-2.1%−1.5 pts

72▼40Carroll County, IAIA20,303-2.2%−2.2 pts

73▲9Monroe County, IAIA7,406-2.3%−1.0 pts

74▲1Page County, IAIA14,856-2.3%−3.0 pts

75▲20Adams County, IAIA3,617-2.3%+5.5 pts

76Keokuk County, IAIA9,797-2.4%−0.4 pts

77▲14Fayette County, IAIA19,047-2.4%−3.1 pts

78▲15Jefferson County, IAIA15,291-2.4%−1.6 pts

79▲5Monona County, IAIA8,539-2.4%−2.3 pts

80▼1Hancock County, IAIA10,528-2.5%+1.8 pts

81▼20Cherokee County, IAIA11,369-2.5%+5.1 pts

82▼15Hardin County, IAIA16,455-2.5%−1.0 pts

83▼25Union County, IAIA11,829-2.5%+0.9 pts

84▼22Chickasaw County, IAIA11,663-2.9%−1.4 pts

85▲9Audubon County, IAIA5,509-2.9%+4.0 pts

86▼3Sac County, IAIA9,525-2.9%+3.5 pts

87▲9Emmet County, IAIA9,107-3.0%+1.7 pts

88▼20Montgomery County, IAIA10,002-3.2%−0.6 pts

89▼63Muscatine County, IAIA41,853-3.2%−7.7 pts

90▼53Ida County, IAIA6,777-3.3%+3.1 pts

91▼14Kossuth County, IAIA14,322-3.4%+4.3 pts

92▼20Osceola County, IAIA5,980-3.4%+0.2 pts

93▼34Pocahontas County, IAIA6,819-3.7%+5.4 pts

94▼74Calhoun County, IAIA9,562-3.7%−0.3 pts

95▼5Lee County, IAIA32,306-3.7%−2.1 pts

96▼16Louisa County, IAIA10,416-3.9%−9.0 pts

97▼54Winnebago County, IAIA10,251-4.0%−0.7 pts

98▼27Floyd County, IAIA14,901-4.6%−3.7 pts

99▼76Henry County, IAIA19,349-5.5%−11.3 pts

SHOWING 1–99 OF 99

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UPDATED 2026-09-11 · DATA: US CENSUS BUREAU POPULATION ESTIMATES