Idaho earthquake risk

44 counties scored 0 rated Very High

Bonneville County has the highest earthquake risk in Idaho, scoring 94.2 out of 100 — rated "Relatively Moderate" by FEMA's National Risk Index.

# County NRI score Rating
1 Bonneville County 94.2 Relatively Moderate
2 Bingham County 88.3 Relatively Low
3 Ada County 88.2 Relatively Low
4 Madison County 87.6 Relatively Low
5 Fremont County 82.9 Relatively Low
6 Bannock County 82.8 Relatively Low
7 Jefferson County 80.6 Relatively Low
8 Custer County 79.3 Relatively Low
9 Kootenai County 79.2 Relatively Low
10 Canyon County 78.8 Relatively Low
11 Teton County 78.3 Relatively Low
12 Cassia County 74.5 Relatively Low
13 Minidoka County 74.3 Relatively Low
14 Twin Falls County 74 Relatively Low
15 Blaine County 73.7 Relatively Low
16 Caribou County 72.1 Relatively Low
17 Franklin County 70.5 Relatively Low
18 Bear Lake County 68.9 Relatively Low
19 Valley County 66.2 Relatively Low
20 Jerome County 58.7 Very Low
21 Gooding County 58.5 Very Low
22 Power County 58.2 Very Low
23 Payette County 55.9 Very Low
24 Bonner County 55.8 Very Low
25 Washington County 53.8 Very Low
26 Lemhi County 53.5 Very Low
27 Gem County 51 Very Low
28 Butte County 45.9 Very Low
29 Latah County 43.6 Very Low
30 Elmore County 42 Very Low
31 Idaho County 40.1 Very Low
32 Boise County 40 Very Low
33 Oneida County 39.8 Very Low
34 Shoshone County 38.4 Very Low
35 Nez Perce County 38.3 Very Low
36 Adams County 37.4 Very Low
37 Owyhee County 34.5 Very Low
38 Lincoln County 32.2 Very Low
39 Clark County 30.9 Very Low
40 Benewah County 26.4 Very Low
41 Boundary County 25.4 Very Low
42 Lewis County 23.4 Very Low
43 Camas County 23.2 Very Low
44 Clearwater County 23 Very Low

Source: FEMA National Risk Index v1.20.0, December 2025. Scores are 0–100 percentile rankings among all US counties. See the methodology page for definitions. Download the full CSV for all counties.

Earthquake risk nationally:

Other hazard risks in Idaho:

Frequently asked questions

What is the highest earthquake risk county in Idaho?

Bonneville County, ID has the highest earthquake risk in Idaho, with a FEMA National Risk Index score of 94.2 out of 100 (rated "Relatively Moderate").

What causes earthquake risk in Idaho?

Earthquake risk reflects expected annual losses from ground shaking. High scores concentrate in California, the Pacific Northwest, Alaska, and the New Madrid Seismic Zone (spanning Missouri, Arkansas, Tennessee, and neighboring states). NOAA's Storm Events Database does not track earthquakes, so recorded event counts are not shown.