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.

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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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

95Lee County, IAIA32,306-3.7%−2.1 pts

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

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

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

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

SHOWING 1–99 OF 99

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UPDATED 2026-08-08 · DATA: US CENSUS BUREAU POPULATION ESTIMATES