Idaho Population By County in 2021 (ACS-5Yrs)

Updated on February 28, 2025.

Based on the US Census ACS-5Yrs estimates, in 2021, the total population of Idaho was 1.81M. Among all Idaho counties, Ada was the most populated county (485.25K), followed by Canyon (227.37K), and then Kootenai (168.32K).

On the other hand, the least populated counties were: Clark (839), Camas (1.04K), and Butte (2.57K).

The chart and table below shows the population of each county and the percentage of Idaho population in each county.

You can see similar information for other states and by state for the United States.

Idaho Population By County in 2021
Idaho Population By County in 2021
Items per page:
0 of 0
County Population % of State Population
Ada 485246 26.79
Adams 4321 0.24
Bannock 86362 4.77
Bear Lake 6327 0.35
Benewah 9509 0.53
Bingham 47540 2.62
Blaine 23868 1.32
Boise 7549 0.42
Bonner 46481 2.57
Bonneville 121771 6.72
Boundary 11966 0.66
Butte 2573 0.14
Camas 1044 0.06
Canyon 227367 12.55
Caribou 7003 0.39
Cassia 24469 1.35
Clark 839 0.05
Clearwater 8719 0.48
Custer 4273 0.24
Elmore 28396 1.57
Franklin 14036 0.78
Fremont 13370 0.74
Gem 18692 1.03
Gooding 15422 0.85
Idaho 16494 0.91
Jefferson 30427 1.68
Jerome 24081 1.33
Kootenai 168317 9.29
Latah 39464 2.18
Lemhi 7948 0.44
Lewis 3613 0.20
Lincoln 5184 0.29
Madison 50979 2.81
Minidoka 21393 1.18
Nez Perce 41820 2.31
Oneida 4514 0.25
Owyhee 11815 0.65
Payette 24928 1.38
Power 7854 0.43
Shoshone 13124 0.72
Teton 11490 0.63
Twin Falls 89128 4.92
Valley 11476 0.63
Washington 10425 0.57