RANKING · 2020 CENSUS · 99 SHOWN OF 99

Fastest shrinking, Iowa counties

Iowa counties with the steepest population decline 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 growing Most densely populated Most sparsely populated Best broadband access Worst broadband access

YEAR2000 2010 2020

RANKPLACESTATEPOPPOPULATION GROWTHVS 2000

01Fremont County, IAIA6,522-11.2%+328%

02Decatur County, IAIA7,655-9.6%−328%

03Ringgold County, IAIA4,642-9.1%−1109%

04Emmet County, IAIA9,107-8.9%+89%

05Adams County, IAIA3,617-8.1%+2%

06Audubon County, IAIA5,509-7.3%+6%

07Jefferson County, IAIA15,291-7.0%+786%

08Taylor County, IAIA5,835-6.7%+204%

09Fayette County, IAIA19,047-6.6%−969%

10Lee County, IAIA32,306-6.4%+292%

11Franklin County, IAIA9,868-6.2%+7%

12Greene County, IAIA8,658-6.1%−289%

13Clayton County, IAIA16,845-6.0%+204%

14Cass County, IAIA12,960-5.9%+102%

15Clinton County, IAIA46,002-5.4%+210%

16Monona County, IAIA8,539-5.3%+3715%

17Sac County, IAIA9,525-5.2%−20%

18Monroe County, IAIA7,406-4.9%+308%

19Van Buren County, IAIA7,131-4.8%−380%

20Louisa County, IAIA10,416-4.8%−195%

21Hancock County, IAIA10,528-4.8%+13%

22Winneshiek County, IAIA19,733-4.7%−311%

23Kossuth County, IAIA14,322-4.6%−40%

24Keokuk County, IAIA9,797-4.5%+136%

25Page County, IAIA14,856-4.5%−820%

26Palo Alto County, IAIA8,899-4.5%−8%

27Appanoose County, IAIA12,077-4.4%+2663%

28Osceola County, IAIA5,980-4.2%+15%

29Floyd County, IAIA14,901-4.1%+348%

30Hamilton County, IAIA14,944-4.0%−277%

31Mills County, IAIA14,793-3.8%−137%

32Montgomery County, IAIA10,002-3.8%+51%

33Hardin County, IAIA16,455-3.7%+153%

34Butler County, IAIA14,049-3.6%+32%

35Tama County, IAIA16,796-3.6%−191%

36Des Moines County, IAIA38,077-3.5%+469%

37Shelby County, IAIA11,689-3.5%+703%

38Chickasaw County, IAIA11,663-3.4%+128%

39Cherokee County, IAIA11,369-3.4%−55%

40Crawford County, IAIA16,237-3.3%−435%

41Pocahontas County, IAIA6,819-3.2%−65%

42Union County, IAIA11,829-3.2%−9%

43Guthrie County, IAIA10,782-3.0%−179%

44Lucas County, IAIA8,847-3.0%−176%

45Webster County, IAIA36,838-2.7%+906%

46Adair County, IAIA7,403-2.4%+23%

47Cerro Gordo County, IAIA42,372-2.3%+279%

48Harrison County, IAIA14,623-2.3%−136%

49Humboldt County, IAIA9,409-2.2%−36%

50Wright County, IAIA12,801-2.2%−575%

51Worth County, IAIA7,338-2.0%+99%

52Mitchell County, IAIA10,650-2.0%+296%

53Benton County, IAIA26,004-1.9%−115%

54Allamakee County, IAIA14,238-1.9%−132%

55Buchanan County, IAIA20,883-1.9%−257%

56Jackson County, IAIA19,288-1.8%−205%

57Winnebago County, IAIA10,251-1.7%−48%

58Clay County, IAIA16,202-1.7%+40%

59Delaware County, IAIA17,674-1.6%−176%

60O'Brien County, IAIA14,220-1.5%−32%

61Marshall County, IAIA39,890-1.3%−149%

62Poweshiek County, IAIA18,368-1.3%+16%

63Ida County, IAIA6,777-1.2%−81%

64Howard County, IAIA9,415-1.0%−181%

65Grundy County, IAIA12,361-1.0%−135%

66Mahaska County, IAIA21,880-0.9%−123%

67Wapello County, IAIA35,210-0.5%−152%

68Carroll County, IAIA20,303-0.3%+2782%

69Cedar County, IAIA18,359+0.0%−99%

70Jones County, IAIA21,253+0.0%−99%

71Black Hawk County, IAIA131,532+0.0%−99%

72Marion County, IAIA34,192+0.3%−95%

73Pottawattamie County, IAIA92,996+0.5%−91%

74Muscatine County, IAIA41,853+1.1%−75%

75Wayne County, IAIA6,738+1.5%−131%

76Boone County, IAIA26,799+1.6%−62%

77Henry County, IAIA19,349+1.7%−71%

78Iowa County, IAIA16,504+1.9%−74%

79Jasper County, IAIA38,153+2.6%−62%

80Calhoun County, IAIA9,562+2.7%−178%

81Buena Vista County, IAIA20,449+2.8%+24%

82Plymouth County, IAIA25,697+2.8%−54%

83Bremer County, IAIA25,296+2.9%+31%

84Lyon County, IAIA12,354+3.0%−293%

85Woodbury County, IAIA106,649+3.7%−35%

86Washington County, IAIA22,667+4.0%−26%

87Davis County, IAIA9,230+4.1%+48%

88Clarke County, IAIA9,574+5.0%−51%

89Madison County, IAIA17,270+5.5%−55%

90Scott County, IAIA175,259+5.7%+12%

91Dubuque County, IAIA99,381+6.0%+89%

92Dickinson County, IAIA18,077+6.2%−39%

93Sioux County, IAIA36,774+6.4%+14%

94Linn County, IAIA232,028+9.0%−34%

95Story County, IAIA101,291+10.0%+30%

96Warren County, IAIA57,331+13.4%+4%

97Polk County, IAIA516,546+14.3%−1%

98Johnson County, IAIA160,044+16.8%+8%

99Dallas County, IAIA118,457+50.7%+37%

SHOWING 1–99 OF 99

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