RANKING · 2025 ESTIMATES · 44 SHOWN OF 44

Most population gained, Idaho counties

Idaho counties that added the most residents from the 2020 census to 2025, by raw count of people rather than percentage. This list covers the 44 counties in Idaho that qualify, ranked against each other statewide. The median across all 44 is +1,085. Biggest climber in the top 100 since 2020: Idaho County, ID, up 12 places to #19.

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SAME RANKING BYCities States Metros

YEAR2000 2010 2020 2025

RANKPLACESTATEPOPPOPULATION CHANGEVS 2000

01Ada County, IDID546,141+51,174−46%

02Canyon County, IDID275,123+44,018+6%

03Kootenai County, IDID191,864+20,502−47%

04Bonneville County, IDID135,771+11,807+14%

05▲1Twin Falls County, IDID97,539+7,493−30%

06▲1Bonner County, IDID54,420+7,310−28%

07▲2Bannock County, IDID91,591+4,573−52%

08Jefferson County, IDID35,297+4,406+69%

09▲5Bingham County, IDID51,153+3,161−24%

10▲3Gem County, IDID21,773+2,650−21%

11▲1Payette County, IDID27,824+2,438−41%

12▲3Latah County, IDID41,842+2,325−46%

13▼8Madison County, IDID55,172+2,259−40%

14▲3Jerome County, IDID26,362+2,125−34%

15▲8Boundary County, IDID13,997+1,941+26%

16▲2Cassia County, IDID26,397+1,742−8%

17▲5Franklin County, IDID15,889+1,695−19%

18▲3Teton County, IDID13,254+1,624−37%

19▲12Idaho County, IDID17,874+1,333−23%

20Minidoka County, IDID22,911+1,298+60%

21▼11Blaine County, IDID25,517+1,245−77%

22▼6Valley County, IDID12,831+1,085−30%

23▲6Washington County, IDID11,583+1,083−24%

24▲8Benewah County, IDID10,508+978−21%

25Shoshone County, IDID14,130+961−701%

26▼2Boise County, IDID8,545+935−70%

27▲7Gooding County, IDID16,446+848−66%

28▲5Fremont County, IDID14,208+820−7%

29▼18Nez Perce County, IDID42,905+815−78%

30▼11Elmore County, IDID29,465+799−90%

31▼4Owyhee County, IDID12,661+748−67%

32▼6Adams County, IDID5,013+634+186%

33▼3Oneida County, IDID5,085+521−18%

34▲3Lemhi County, IDID8,474+500−45%

35▲5Lincoln County, IDID5,603+476−35%

36▲2Clearwater County, IDID9,118+384−10%

37▼1Power County, IDID8,246+368−19%

38▲3Custer County, IDID4,636+361+73%

39▼11Bear Lake County, IDID6,727+355+9%

40▼1Camas County, IDID1,316+239−9%

41▼6Caribou County, IDID7,252+225−34%

42▲2Butte County, IDID2,783+209−1200%

43Lewis County, IDID3,704+171−26%

44▼2Clark County, IDID783-7−103%

SHOWING 1–44 OF 44

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UPDATED 2026-09-11 · DATA: US CENSUS BUREAU POPULATION ESTIMATES