RANKING · 2010 CENSUS · 44 SHOWN OF 44

Youngest by median age, Idaho counties · 2010

Idaho counties with the youngest median age (2010 ACS). This list covers the 44 counties in Idaho that qualify, ranked against each other statewide. The median across all 44 is 37.7.

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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

01Madison County, IDID55,17222.6+9%

02Latah County, IDID41,84228.3+1%

03Elmore County, IDID29,46530.0+3%

04Jefferson County, IDID35,29730.0+4%

05Bannock County, IDID91,59131.4+5%

06Franklin County, IDID15,88931.5+14%

07Canyon County, IDID275,12331.6+4%

08Bonneville County, IDID135,77131.70%

09Jerome County, IDID26,36231.7−4%

10Bingham County, IDID51,15331.8+7%

11Cassia County, IDID26,39732.0+3%

12Lincoln County, IDID5,60332.0−7%

13Clark County, IDID78332.7+7%

14Power County, IDID8,24633.2+5%

15Teton County, IDID13,25433.2+6%

16Fremont County, IDID14,20833.5+5%

17Gooding County, IDID16,44634.3−2%

18Twin Falls County, IDID97,53934.4−1%

19Ada County, IDID546,14134.8+6%

20Minidoka County, IDID22,91135.3+5%

21Owyhee County, IDID12,66136.0+9%

22Payette County, IDID27,82437.2+8%

23Caribou County, IDID7,25237.7+8%

24Kootenai County, IDID191,86438.9+8%

25Oneida County, IDID5,08539.1+9%

26Blaine County, IDID25,51740.4+8%

27Bear Lake County, IDID6,72740.5+13%

28Nez Perce County, IDID42,90540.8+7%

29Butte County, IDID2,78341.7+7%

30Boundary County, IDID13,99742.8+12%

31Gem County, IDID21,77342.9+14%

32Washington County, IDID11,58343.6+11%

33Camas County, IDID1,31644.3+12%

34Benewah County, IDID10,50844.8+14%

35Bonner County, IDID54,42045.8+12%

36Shoshone County, IDID14,13046.2+11%

37Valley County, IDID12,83146.9+8%

38Custer County, IDID4,63648.0+17%

39Idaho County, IDID17,87448.0+13%

40Lewis County, IDID3,70448.0+13%

41Boise County, IDID8,54548.4+20%

42Clearwater County, IDID9,11849.0+18%

43Lemhi County, IDID8,47449.7+16%

44Adams County, IDID5,01350.0+13%

SHOWING 1–44 OF 44

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