RANKING · 2010 CENSUS · 102 SHOWN OF 102

Youngest by median age, Illinois counties · 2010

Illinois counties with the youngest median age (2010 ACS). This list covers the 102 counties in Illinois that qualify, ranked against each other statewide. The median across all 102 is 41.6.

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SAME RANKING BYCities States Metros ZIP codes

RELATEDLargest foreign-born population Most residents with a disability Largest veteran population Most uninsured people Largest senior population Most unmarried people

YEAR1990 2000 2010 2020 2024

RANKPLACESTATEPOPMEDIAN AGEVS 2000

01Champaign County, ILIL209,97228.9+1%

02McDonough County, ILIL25,91628.90%

03Jackson County, ILIL52,50129.1+6%

04DeKalb County, ILIL101,83529.3+3%

05Coles County, ILIL46,60731.6+3%

06McLean County, ILIL171,41932.1+5%

07Kendall County, ILIL145,47032.9−4%

08Kane County, ILIL525,75734.5+7%

09Cook County, ILIL5,194,62535.3+5%

10Will County, ILIL712,25335.4+6%

11Grundy County, ILIL54,05236.1−1%

12Kankakee County, ILIL105,52536.7+4%

13Lake County, ILIL719,33936.7+9%

14Boone County, ILIL53,56836.8+7%

15Peoria County, ILIL178,55336.8+2%

16St. Clair County, ILIL250,70836.9+5%

17Brown County, ILIL6,40137.3+6%

18McHenry County, ILIL317,75138.0+11%

19DuPage County, ILIL934,29838.2+9%

20Winnebago County, ILIL283,67438.3+7%

21Madison County, ILIL263,11038.6+5%

22Cass County, ILIL12,46338.7+4%

23Douglas County, ILIL19,88038.7+3%

24Sangamon County, ILIL194,17039.2+5%

25Effingham County, ILIL34,51939.2+10%

26Clinton County, ILIL37,12839.3+7%

27Logan County, ILIL27,18239.4+6%

28Perry County, ILIL20,16039.4+5%

29Warren County, ILIL16,22239.6+5%

30Woodford County, ILIL38,11139.6+5%

31Lawrence County, ILIL13,79039.7−3%

32Bond County, ILIL16,95939.7+8%

33Tazewell County, ILIL130,04939.8+4%

34Vermilion County, ILIL71,25939.8+5%

35Fayette County, ILIL20,79039.9+6%

36Rock Island County, ILIL141,86940.0+6%

37Williamson County, ILIL67,22540.1+3%

38Macon County, ILIL99,30040.3+6%

39Moultrie County, ILIL14,37140.3+4%

40Jersey County, ILIL21,16040.5+9%

41Jefferson County, ILIL36,14740.6+8%

42Adams County, ILIL64,26740.7+6%

43Ogle County, ILIL51,39940.7+9%

44Livingston County, ILIL35,05740.8+9%

45Morgan County, ILIL32,51540.8+8%

46Cumberland County, ILIL10,20840.9+10%

47Monroe County, ILIL34,84041.0+9%

48LaSalle County, ILIL107,77341.0+8%

49Randolph County, ILIL29,92141.0+9%

50Alexander County, ILIL4,57041.1+8%

51Marion County, ILIL36,38241.4+8%

52Christian County, ILIL33,44341.6+7%

53Greene County, ILIL11,31341.6+10%

54Crawford County, ILIL18,64841.7+8%

55Saline County, ILIL22,77241.7+5%

56De Witt County, ILIL15,11841.7+8%

57Macoupin County, ILIL43,74841.7+7%

58Franklin County, ILIL36,91641.8+4%

59Henry County, ILIL48,09541.8+7%

60Whiteside County, ILIL54,12141.8+9%

61Fulton County, ILIL32,90141.9+7%

62Montgomery County, ILIL28,07641.9+10%

63Knox County, ILIL47,76742.0+7%

64Lee County, ILIL32,91442.0+11%

65Wabash County, ILIL10,90742.0+8%

66Massac County, ILIL13,50242.1+6%

67Richland County, ILIL15,21942.1+8%

68Clay County, ILIL12,79342.2+6%

69Johnson County, ILIL13,36342.2+15%

70Clark County, ILIL15,11442.3+8%

71Washington County, ILIL13,56442.3+9%

72Ford County, ILIL13,21642.4+8%

73Bureau County, ILIL32,51042.5+7%

74Pike County, ILIL14,23142.5+7%

75Menard County, ILIL11,86342.6+12%

76Piatt County, ILIL16,79142.6+8%

77Edwards County, ILIL5,89842.7+5%

78Jasper County, ILIL9,03242.7+12%

79Scott County, ILIL4,86642.7+10%

80Union County, ILIL16,65642.9+6%

81Wayne County, ILIL15,88242.9+8%

82Hamilton County, ILIL7,85943.1+6%

83Stephenson County, ILIL43,22043.1+12%

84Edgar County, ILIL16,32343.2+10%

85Pulaski County, ILIL4,82043.2+15%

86Iroquois County, ILIL26,15043.4+10%

87Shelby County, ILIL20,57643.5+11%

88Schuyler County, ILIL6,65743.6+7%

89Mercer County, ILIL15,22943.7+11%

90Stark County, ILIL5,31943.8+10%

91Mason County, ILIL12,41144.0+11%

92Gallatin County, ILIL4,61644.4+9%

93Calhoun County, ILIL4,30044.6+10%

94Hancock County, ILIL16,80344.6+11%

95Marshall County, ILIL11,47344.8+10%

96Putnam County, ILIL5,61945.2+14%

97White County, ILIL13,25045.2+8%

98Hardin County, ILIL3,58846.3+10%

99Carroll County, ILIL15,41946.5+14%

100Pope County, ILIL3,67246.6+13%

101Jo Daviess County, ILIL21,59447.1+13%

102Henderson County, ILIL5,98447.2+15%

SHOWING 1–102 OF 102

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UPDATED 2026-09-11 · DATA: US CENSUS BUREAU DECENNIAL CENSUS