RANKING · 2020 CENSUS · 44 SHOWN OF 44

Most sparsely populated, Idaho counties · 2020

Idaho counties with the fewest residents per square mile (2020). This list covers the 44 counties in Idaho that qualify, ranked against each other statewide. The median across all 44 is 10.

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SAME RANKING BYCities States Metros

RELATEDLargest by population Fastest growing Fastest shrinking Most population gained Most population lost Most densely populated

YEAR1990 2000 2010 2020 2025

RANKPLACESTATEPOPPOPULATION DENSITYVS 2000

01Clark County, IDID7830−23%

02Custer County, IDID4,6361−2%

03Camas County, IDID1,3161+9%

04Butte County, IDID2,7831−11%

05Owyhee County, IDID12,6612+12%

06Lemhi County, IDID8,4742+2%

07Idaho County, IDID17,8742+7%

08Valley County, IDID12,8313+54%

09Adams County, IDID5,0133+26%

10Clearwater County, IDID9,1184−2%

11Oneida County, IDID5,0854+11%

12Caribou County, IDID7,2524−4%

13Boise County, IDID8,5454+14%

14Lincoln County, IDID5,6034+27%

15Shoshone County, IDID14,1305−4%

16Power County, IDID8,2466+5%

17Bear Lake County, IDID6,7277−1%

18Fremont County, IDID14,2087+13%

19Washington County, IDID11,5837+5%

20Lewis County, IDID3,7047−6%

21Blaine County, IDID25,5179+28%

22Elmore County, IDID29,4659−2%

23Boundary County, IDID13,99710+22%

24Cassia County, IDID26,39710+15%

25Benewah County, IDID10,50812+4%

26Gooding County, IDID16,44621+10%

27Franklin County, IDID15,88921+25%

28Bingham County, IDID51,15323+15%

29Teton County, IDID13,25426+94%

30Bonner County, IDID54,42027+28%

31Jefferson County, IDID35,29728+61%

32Minidoka County, IDID22,91129+7%

33Gem County, IDID21,77334+26%

34Latah County, IDID41,84237+13%

35Jerome County, IDID26,36241+32%

36Twin Falls County, IDID97,53947+40%

37Nez Perce County, IDID42,90550+13%

38Payette County, IDID27,82462+23%

39Bonneville County, IDID135,77166+50%

40Bannock County, IDID91,59178+15%

41Madison County, IDID55,172113+93%

42Kootenai County, IDID191,864138+58%

43Canyon County, IDID275,123394+76%

44Ada County, IDID546,141470+64%

SHOWING 1–44 OF 44

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