RANKING · 2025 ESTIMATES · 44 SHOWN OF 44

Most sparsely populated, Idaho counties

Idaho counties with the fewest residents per square mile (2025). This list covers the 44 counties in Idaho that qualify, ranked against each other statewide.

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RANKPLACESTATEPOPPOPULATION DENSITYVS –

01Clark County, IDID7830–

02Custer County, IDID4,6361–

03Camas County, IDID1,3161–

04Butte County, IDID2,7831–

05Owyhee County, IDID12,6612–

06Lemhi County, IDID8,4742–

07Idaho County, IDID17,8742–

08Valley County, IDID12,8314–

09Adams County, IDID5,0134–

10Clearwater County, IDID9,1184–

11Caribou County, IDID7,2524–

12Oneida County, IDID5,0854–

13Boise County, IDID8,5454–

14Lincoln County, IDID5,6035–

15Shoshone County, IDID14,1305–

16Power County, IDID8,2466–

17Bear Lake County, IDID6,7277–

18Fremont County, IDID14,2088–

19Lewis County, IDID3,7048–

20Washington County, IDID11,5838–

21Elmore County, IDID29,46510–

22Blaine County, IDID25,51710–

23Cassia County, IDID26,39710–

24Boundary County, IDID13,99711–

25Benewah County, IDID10,50814–

26Gooding County, IDID16,44623–

27Franklin County, IDID15,88924–

28Bingham County, IDID51,15324–

29Teton County, IDID13,25430–

30Minidoka County, IDID22,91130–

31Bonner County, IDID54,42031–

32Jefferson County, IDID35,29732–

33Latah County, IDID41,84239–

34Gem County, IDID21,77339–

35Jerome County, IDID26,36244–

36Nez Perce County, IDID42,90551–

37Twin Falls County, IDID97,53951–

38Payette County, IDID27,82468–

39Bonneville County, IDID135,77173–

40Bannock County, IDID91,59182–

41Madison County, IDID55,172118–

42Kootenai County, IDID191,864155–

43Canyon County, IDID275,123469–

44Ada County, IDID546,141519–

SHOWING 1–44 OF 44

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UPDATED 2026-07-15 · DATA: US CENSUS BUREAU POPULATION ESTIMATES