Records
2
Earthquakes in Idaho
73 earthquakes (M4+) recorded in Idaho between 2005-2025. Data from USGS.
Idaho has recorded 73 earthquakes of magnitude 4.0 or greater between 2005 and 2025, including 1 significant events at M6.0 or above. The strongest quake reached magnitude 6.5 near The 1983 Borah Peak Earthquake, Idaho. The most active year on record was 2020, with 1 events.
Seismic Profile of Idaho
Idaho: 73 M4+ events (2005–2025) — 1 significant (M6+), strongest M6.5 near The 1983 Borah Peak Earthquake, Idaho, avg magnitude 4.3, ~37 M4+ events/year across 2 active years. Depth profile: 2 shallow / 0 intermediate / 0 deep (100% shallow). Peak year: 2020 (1 events). USGS catalog scope + ShakeMap methodology →
How to read these figures: every count on this page comes from the USGS Comprehensive Earthquake Catalog (ComCat), the federal record of more than 1,000 instrumentally measured events logged across the United States since 2005. A higher total does not always mean a state faces more danger, because catalog totals reflect both genuine activity and the density of seismic stations that detect smaller tremors. Shallow events under 70 kilometers deep produce the strongest surface shaking for a given magnitude, so the shallow share above matters as much as the raw count when you gauge real-world risk. Magnitude values can be revised for weeks after an event as analysts refine waveform data, which is why our maximum and average figures may differ slightly from a first headline. For the authoritative, site-specific hazard estimate behind any building decision, consult the USGS National Seismic Hazard Model rather than these summary statistics. Our methodology page documents the exact query, the 2005 to 2025 window, and the magnitude thresholds used here.
Total Earthquakes
73
Significant (M6+)
1
Maximum Magnitude
6.5
Avg Magnitude
4.3
Coverage
2005-2025
Source
USGS ComCat
Shallow event share (<70 km depth) 100.0%
USGS PGA Hazard Tier — Idaho
PGA hazard tier estimate for Idaho — Idaho (USGS NSHM)
Tier estimate derived from Idaho's catalog rank and maximum magnitude. For the authoritative site-specific PGA, query the USGS Unified Hazard Tool.
Seismic Activity in Idaho
Idaho has experienced 73 earthquakes of magnitude 4.0 or greater since 2005, based on data from the U.S. Geological Survey (USGS) Comprehensive Earthquake Catalog. Of these, 1 were significant events reaching magnitude 6.0 or above — the threshold where structural damage becomes likely. The strongest recorded event reached magnitude 6.5.
Seismic activity in Idaho has varied over the recording period, with 2 years of data available. Understanding historical patterns helps communities prepare through building codes, emergency plans, and public awareness.
Events by Year
2020
1
1983
1
Significant Earthquakes (2)
| Mag | Location | Depth | Date |
|---|---|---|---|
| 6.5 | Stanley, Idaho | 12.1 km | Mar 31, 2020 |
| 6.9 | The 1983 Borah Peak Earthquake, Idaho | 10.0 km | Oct 28, 1983 |
Learn More About Earthquakes
Guides to help you understand earthquake data, preparedness, and risk.
Related Data for Idaho
Explore hazard, climate, and insurance data from other federal sources. Storm and climate datasets originate with the NOAA National Centers for Environmental Information; you can also browse the source NOAA Storm Events Database directly.
Source: USGS ComCat (Comprehensive Earthquake Catalog) + USGS National Seismic Hazard Model + FEMA NEHRP USGS earthquake event catalog for Idaho + 2023 USGS National Seismic Hazard Model PGA classes (FEMA Seismic Design Categories A-F) · 2024 USGS ComCat updated continuously; magnitude/depth/location revised as analysis evolves. Seismic hazard model published in 2023, applies to 50-year, 2% probability-of-exceedance ground motion estimates.
Frequently Asked Questions
How many earthquakes have occurred in Idaho? ▼
Idaho has recorded 73 earthquakes of magnitude 4.0 or greater between 2005 and 2025, with 1 significant events (M6+). The average magnitude of recorded events is 4.3.
What was the largest earthquake in Idaho? ▼
The largest recorded earthquake in Idaho (2005-2025) was a magnitude 6.9 event near The 1983 Borah Peak Earthquake, Idaho on Oct 28, 1983. It occurred at a depth of 10.0 km.
Is Idaho at risk for earthquakes? ▼
Idaho has significant seismic activity with 73 recorded events (M4+) in the USGS dataset. Earthquake risk depends on proximity to fault lines, soil conditions, and building standards. USGS maintains real-time monitoring at earthquake.usgs.gov.
How often do earthquakes happen in Idaho? ▼
Based on USGS data from 2005 to 2025, Idaho averages approximately 37 earthquakes (M4+) per year. The most seismically active year was 2020 with 1 recorded events. Frequency can vary significantly from year to year depending on tectonic stress and fault activity.
How deep are earthquakes in Idaho? ▼
The average earthquake depth in Idaho is 11.0 km. 2 events (100%) were shallow (under 70 km), which tend to cause the most surface damage. Shallow earthquakes generally produce stronger ground shaking than deeper ones of similar magnitude.
Does Idaho have earthquake building codes? ▼
Building codes in Idaho follow standards set by the International Building Code (IBC), which incorporates USGS seismic hazard maps. Given Idaho's significant seismic activity (73 events M4+), structures are required to meet enhanced seismic design requirements. Specific requirements vary by jurisdiction and structure type.
Data Sources
Primary Source: U.S. Geological Survey (USGS), Earthquake Hazards Program, Comprehensive Earthquake Catalog (ComCat), 2005–2025. Includes all seismic events of magnitude 4.0 and above within Idaho. Data accessed via USGS Earthquake API.
Methodology: Magnitude values follow the moment magnitude scale (Mw). Depth is measured in kilometers from the surface. Events are classified as shallow (<70 km), intermediate (70–300 km), or deep (>300 km).
Read our methodology — how this data is sourced, computed, and verified.
Related
Data sourced from official U.S. government datasets. See our methodology for details. Retrieved and formatted by PlainQuake Editorial