RANKING · 2000 CENSUS · 44 SHOWN OF 44

Youngest by median age, Idaho counties · 2000

Idaho counties with the youngest median age (2000 ACS). This list covers the 44 counties in Idaho that qualify, ranked against each other statewide. The median across all 44 is 35.1.

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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 1990

01Madison County, IDID55,17220.7+4%

02Franklin County, IDID15,88927.70%

03Latah County, IDID41,84227.9+2%

04Jefferson County, IDID35,29728.8+9%

05Elmore County, IDID29,46529.1+4%

06Bingham County, IDID51,15329.7+6%

07Bannock County, IDID91,59129.80%

08Canyon County, IDID275,12330.5−3%

09Clark County, IDID78330.7−6%

10Cassia County, IDID26,39731.1+7%

11Teton County, IDID13,25431.3+2%

12Power County, IDID8,24631.6+5%

13Bonneville County, IDID135,77131.8+10%

14Fremont County, IDID14,20831.9+13%

15Ada County, IDID546,14132.8+3%

16Jerome County, IDID26,36232.9+1%

17Owyhee County, IDID12,66132.9+7%

18Minidoka County, IDID22,91133.5+11%

19Lincoln County, IDID5,60334.3−2%

20Payette County, IDID27,82434.40%

21Twin Falls County, IDID97,53934.9+5%

22Caribou County, IDID7,25235.0+14%

23Gooding County, IDID16,44635.1+1%

24Bear Lake County, IDID6,72735.8+15%

25Oneida County, IDID5,08536.0+16%

26Kootenai County, IDID191,86436.1+3%

27Blaine County, IDID25,51737.4+12%

28Gem County, IDID21,77337.5+4%

29Nez Perce County, IDID42,90538.1+7%

30Boundary County, IDID13,99738.3+17%

31Butte County, IDID2,78338.8+17%

32Benewah County, IDID10,50839.2+13%

33Washington County, IDID11,58339.2+6%

34Camas County, IDID1,31639.7+8%

35Boise County, IDID8,54540.4+13%

36Bonner County, IDID54,42040.8+11%

37Custer County, IDID4,63641.2+19%

38Clearwater County, IDID9,11841.7+10%

39Shoshone County, IDID14,13041.8+12%

40Idaho County, IDID17,87442.3+16%

41Lewis County, IDID3,70442.5+17%

42Lemhi County, IDID8,47442.7+12%

43Valley County, IDID12,83143.5+17%

44Adams County, IDID5,01344.4+23%

SHOWING 1–44 OF 44

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