RANKING · 2000 CENSUS · 99 SHOWN OF 99

Fastest growing, Iowa counties · 2000

Iowa counties ranked by population growth since the prior decennial census. 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 densely populated Most sparsely populated Best broadband access Worst broadband access

YEAR2000 2010 2020

RANKPLACESTATEPOPPOPULATION GROWTHVS 2000

01Dallas County, IAIA118,457+37.0%+0%

02Johnson County, IAIA160,044+15.5%+0%

03Polk County, IAIA516,546+14.5%+0%

04Linn County, IAIA232,028+13.6%+0%

05Warren County, IAIA57,331+12.9%+0%

06Benton County, IAIA26,004+12.8%+0%

07Madison County, IAIA17,270+12.3%+0%

08Clarke County, IAIA9,574+10.2%+0%

09Mills County, IAIA14,793+10.2%+0%

10Dickinson County, IAIA18,077+10.2%+0%

11Story County, IAIA101,291+7.7%+0%

12Iowa County, IAIA16,504+7.1%+0%

13Jasper County, IAIA38,153+6.9%+0%

14Marion County, IAIA34,192+6.8%+0%

15Harrison County, IAIA14,623+6.4%+0%

16Plymouth County, IAIA25,697+6.2%+0%

17Pottawattamie County, IAIA92,996+6.1%+0%

18Allamakee County, IAIA14,238+5.9%+0%

19Henry County, IAIA19,349+5.8%+0%

20Woodbury County, IAIA106,649+5.7%+0%

21Sioux County, IAIA36,774+5.6%+0%

22Washington County, IAIA22,667+5.4%+0%

23Louisa County, IAIA10,416+5.1%+0%

24Scott County, IAIA175,259+5.1%+0%

25Cedar County, IAIA18,359+4.6%+0%

26Muscatine County, IAIA41,853+4.5%+0%

27Decatur County, IAIA7,655+4.2%+0%

28Boone County, IAIA26,799+4.1%+0%

29Jones County, IAIA21,253+4.0%+0%

30Tama County, IAIA16,796+3.9%+0%

31Lucas County, IAIA8,847+3.9%+0%

32Guthrie County, IAIA10,782+3.8%+0%

33Mahaska County, IAIA21,880+3.8%+0%

34Black Hawk County, IAIA131,532+3.4%+0%

35Greene County, IAIA8,658+3.2%+0%

36Dubuque County, IAIA99,381+3.2%+0%

37Grundy County, IAIA12,361+2.8%+0%

38Davis County, IAIA9,230+2.8%+0%

39Marshall County, IAIA39,890+2.7%+0%

40Hamilton County, IAIA14,944+2.3%+0%

41Bremer County, IAIA25,296+2.2%+0%

42Buena Vista County, IAIA20,449+2.2%+0%

43Winneshiek County, IAIA19,733+2.2%+0%

44Delaware County, IAIA17,674+2.0%+0%

45Jackson County, IAIA19,288+1.7%+0%

46Van Buren County, IAIA7,131+1.7%+0%

47Howard County, IAIA9,415+1.3%+0%

48Buchanan County, IAIA20,883+1.2%+0%

49Wapello County, IAIA35,210+1.0%+0%

50Crawford County, IAIA16,237+1.0%+0%

51Ringgold County, IAIA4,642+0.9%+0%

52Fayette County, IAIA19,047+0.8%+0%

53Page County, IAIA14,856+0.6%+0%

54Wright County, IAIA12,801+0.5%+0%

55Carroll County, IAIA20,303-0.0%+0%

56Monona County, IAIA8,539-0.1%+0%

57Appanoose County, IAIA12,077-0.2%+0%

58Webster County, IAIA36,838-0.3%+0%

59Shelby County, IAIA11,689-0.4%+0%

60Mitchell County, IAIA10,650-0.5%+0%

61Cerro Gordo County, IAIA42,372-0.6%+0%

62Des Moines County, IAIA38,077-0.6%+0%

63Jefferson County, IAIA15,291-0.8%+0%

64Floyd County, IAIA14,901-0.9%+0%

65Worth County, IAIA7,338-1.0%+0%

66Poweshiek County, IAIA18,368-1.1%+0%

67Monroe County, IAIA7,406-1.2%+0%

68Clay County, IAIA16,202-1.2%+0%

69Hardin County, IAIA16,455-1.5%+0%

70Chickasaw County, IAIA11,663-1.5%+0%

71Lyon County, IAIA12,354-1.6%+0%

72Lee County, IAIA32,306-1.6%+0%

73Clinton County, IAIA46,002-1.7%+0%

74Keokuk County, IAIA9,797-1.9%+0%

75Clayton County, IAIA16,845-2.0%+0%

76Adair County, IAIA7,403-2.0%+0%

77Taylor County, IAIA5,835-2.2%+0%

78O'Brien County, IAIA14,220-2.2%+0%

79Montgomery County, IAIA10,002-2.5%+0%

80Fremont County, IAIA6,522-2.6%+0%

81Butler County, IAIA14,049-2.7%+0%

82Cass County, IAIA12,960-2.9%+0%

83Winnebago County, IAIA10,251-3.3%+0%

84Calhoun County, IAIA9,562-3.4%+0%

85Union County, IAIA11,829-3.5%+0%

86Humboldt County, IAIA9,409-3.5%+0%

87Osceola County, IAIA5,980-3.6%+0%

88Hancock County, IAIA10,528-4.3%+0%

89Emmet County, IAIA9,107-4.7%+0%

90Wayne County, IAIA6,738-4.8%+0%

91Palo Alto County, IAIA8,899-4.9%+0%

92Franklin County, IAIA9,868-5.8%+0%

93Ida County, IAIA6,777-6.3%+0%

94Sac County, IAIA9,525-6.5%+0%

95Audubon County, IAIA5,509-6.9%+0%

96Cherokee County, IAIA11,369-7.5%+0%

97Kossuth County, IAIA14,322-7.7%+0%

98Adams County, IAIA3,617-7.9%+0%

99Pocahontas County, IAIA6,819-9.1%+0%

SHOWING 1–99 OF 99

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UPDATED 2026-06-02 · DATA: US CENSUS BUREAU ACS 5-YEAR ESTIMATES