New Hampshire earthquake risk
Hillsborough County has the highest earthquake risk in New Hampshire, scoring 88.2 out of 100 — rated "Relatively Low" by FEMA's National Risk Index.
| # | County | NRI score | Rating |
|---|---|---|---|
| 1 | Hillsborough County | 88.2 | Relatively Low |
| 2 | Rockingham County | 87.5 | Relatively Low |
| 3 | Strafford County | 77.4 | Relatively Low |
| 4 | Merrimack County | 76.1 | Relatively Low |
| 5 | Grafton County | 69.6 | Relatively Low |
| 6 | Carroll County | 62.8 | Relatively Low |
| 7 | Belknap County | 59.8 | Relatively Low |
| 8 | Cheshire County | 58 | Very Low |
| 9 | Coos County | 49 | Very Low |
| 10 | Sullivan County | 43.1 | 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 New Hampshire:
Frequently asked questions
What is the highest earthquake risk county in New Hampshire?
Hillsborough County, NH has the highest earthquake risk in New Hampshire, with a FEMA National Risk Index score of 88.2 out of 100 (rated "Relatively Low").
What causes earthquake risk in New Hampshire?
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.