I-84 in Idaho: fatal crashes
From 2015 to 2024, 187 fatal crashes on I-84 in Idaho killed 204 people, the most of any numbered road in Idaho. In 2024 there were 15 fatal crashes and 15 deaths on the road.
An interstate running through 9 counties of Idaho. All fatal crashes in Idaho. I-84 in every state.
Deaths on I-84 in Idaho by year
| Year | Fatal crashes | Deaths |
|---|---|---|
| 2024 | 15 | 15 |
| 2023 | 18 | 19 |
| 2022 | 13 | 13 |
| 2021 | 21 | 22 |
| 2020 | 13 | 15 |
| 2019 | 16 | 18 |
| 2018 | 21 | 26 |
| 2017 | 22 | 24 |
| 2016 | 32 | 33 |
| 2015 | 16 | 19 |
Source: NHTSA Fatality Analysis Reporting System (FARS), 2024 Annual Report File (released April 2026, subject to revision). How we count
Where on I-84 in Idaho: the counties with the most fatal crashes
Elmore County had the most fatal crashes on I-84 from 2015 to 2024: 45, with 47 deaths. Elmore, Ada and Jerome counties together held 62% of fatal crashes on I-84 in Idaho from 2015 to 2024; the 8 listed held 99%. Counties are listed from 5 fatal crashes.
| County | 2024 | 2015 to 2024 | Deaths | |
|---|---|---|---|---|
| 1 | Elmore County | 2 | 45 | 47 |
| 2 | Ada County | 3 | 38 | 43 |
| 3 | Jerome County | 2 | 33 | 36 |
| 4 | Canyon County | 1 | 21 | 22 |
| 5 | Payette County | 3 | 16 | 18 |
| 6 | Gooding County | 3 | 13 | 14 |
| 7 | Cassia County | 0 | 10 | 11 |
| 8 | Minidoka County | 1 | 10 | 11 |
Source: NHTSA Fatality Analysis Reporting System (FARS), 2024 Annual Report File (released April 2026, subject to revision). How we count
When fatal crashes happen on I-84 in Idaho
The heaviest slot is Tuesday, noon to 4 pm, with 11 fatal crashes from 2015 to 2024. The worst hour is 3 pm to 4 pm; the worst month is August.
| Midnight to 4 | 4 to 8 am | 8 to noon | Noon to 4 | 4 to 8 pm | 8 to midnight | |
|---|---|---|---|---|---|---|
| Sun | 2.1 percent, 4 fatal crashes | 1.1 percent, 2 fatal crashes | 1.6 percent, 3 fatal crashes | 1.6 percent, 3 fatal crashes | 3.7 percent, 7 fatal crashes | 0.0 percent, 0 fatal crashes |
| Mon | 1.6 percent, 3 fatal crashes | 1.6 percent, 3 fatal crashes | 2.1 percent, 4 fatal crashes | 1.1 percent, 2 fatal crashes | 2.1 percent, 4 fatal crashes | 2.7 percent, 5 fatal crashes |
| Tue | 2.1 percent, 4 fatal crashes | 4.8 percent, 9 fatal crashes | 2.1 percent, 4 fatal crashes | 5.9 percent, 11 fatal crashes | 1.6 percent, 3 fatal crashes | 0.0 percent, 0 fatal crashes |
| Wed | 2.7 percent, 5 fatal crashes | 3.2 percent, 6 fatal crashes | 2.7 percent, 5 fatal crashes | 4.8 percent, 9 fatal crashes | 1.1 percent, 2 fatal crashes | 2.7 percent, 5 fatal crashes |
| Thu | 2.7 percent, 5 fatal crashes | 1.6 percent, 3 fatal crashes | 1.1 percent, 2 fatal crashes | 2.1 percent, 4 fatal crashes | 0.5 percent, 1 fatal crash | 1.1 percent, 2 fatal crashes |
| Fri | 2.7 percent, 5 fatal crashes | 2.1 percent, 4 fatal crashes | 2.7 percent, 5 fatal crashes | 2.1 percent, 4 fatal crashes | 4.3 percent, 8 fatal crashes | 3.2 percent, 6 fatal crashes |
| Sat | 1.6 percent, 3 fatal crashes | 1.6 percent, 3 fatal crashes | 3.2 percent, 6 fatal crashes | 3.7 percent, 7 fatal crashes | 4.3 percent, 8 fatal crashes | 4.3 percent, 8 fatal crashes |
By hour
By month
- Jan9.1%
- Feb1.6%
- Mar9.1%
- Apr7.5%
- May7.0%
- Jun9.1%
- Jul9.1%
- Aug11.8%
- Sep10.2%
- Oct8.0%
- Nov7.5%
- Dec10.2%
Source: NHTSA Fatality Analysis Reporting System (FARS), 2024 Annual Report File (released April 2026, subject to revision). How we count
Fatal crashes per mile on I-84 in Idaho
6.8 fatal crashes a year per 100 miles over 2015 to 2024, on 276 miles of I-84 in Idaho, against 5.8 for all interstates in Idaho. That ranks 1 of 2 interstates in Idaho and 103 of 172 interstate pages on this site.
Mileage from the FHWA Interstate route log (table 1), the only figure here not counted from FARS. Crashes per mile of road, not per vehicle: FARS records crashes, not traffic.
What fatal crashes on I-84 in Idaho first hit
The first harmful event was a rollover in 35%; a collision with another vehicle in 29%, a fixed object such as a tree, pole or barrier in 18%, a pedestrian in 9.6%.
| First harmful event | Fatal crashes | Share |
|---|---|---|
| Rollover | 66 | 35% |
| Collision with another vehicle | 54 | 29% |
| Fixed object (tree, pole, barrier, ditch) | 34 | 18% |
| Pedestrian | 18 | 9.6% |
| Other | 9 | 4.8% |
| Parked vehicle | 6 | 3.2% |
| Cyclist | 0 | 0.0% |
| Not reported | 0 | 0.0% |
Source: NHTSA Fatality Analysis Reporting System (FARS), 2024 Annual Report File (released April 2026, subject to revision). How we count
How fatal crashes on I-84 in Idaho compare with the state
The largest difference from Idaho: from 2015 to 2024, 0.5% of fatal crashes on I-84 in Idaho were at or near an intersection, against 21% across Idaho. Below the Idaho share: drinking drivers and motorcycles. Shares of fatal crashes from 2015 to 2024, against the share across all of Idaho. A share is only given over 20 crashes; above or below means more than chance would give on 187 crashes.
| I-84 | Idaho | ||
|---|---|---|---|
| On rural stretches | 78% | 75% | about the same as the Idaho share |
| At or near an intersection | 0.5% | 21% | below the Idaho share |
| In the dark, road unlit | 33% | 27% | about the same as the Idaho share |
| A drinking driver | 18% | 31% | below the Idaho share |
| Speeding | 20% | 22% | about the same as the Idaho share |
| A distracted driver (as recorded) | 14% | 15% | about the same as the Idaho share |
| Occupants killed unbelted | 56% | 58% | about the same as the Idaho share |
| Hit-and-run | 2.1% | 1.7% | about the same as the Idaho share |
| A motorcycle involved | 5.9% | 14% | below the Idaho share |
| Pedestrians among the dead | 9.8% | 6.9% | about the same as the Idaho share |
Source: NHTSA Fatality Analysis Reporting System (FARS), 2024 Annual Report File (released April 2026, subject to revision). How we count
Questions about fatal crashes on I-84 in Idaho
- How many fatal crashes have there been on I-84 in Idaho?
- 187 fatal crashes killed 204 people on I-84 in Idaho from 2015 to 2024. In 2024 there were 15 fatal crashes and 15 deaths. Source: NHTSA's Fatality Analysis Reporting System (FARS).
- Where on I-84 in Idaho do the most fatal crashes happen?
- Elmore County had the most fatal crashes on I-84 from 2015 to 2024: 45, with 47 deaths. Ada County was second with 38.
- When do fatal crashes on I-84 in Idaho happen most often?
- The heaviest slot from 2015 to 2024 was Tuesday, noon to 4 pm, with 11 fatal crashes.
- How dangerous is I-84 in Idaho per mile?
- 6.8 fatal crashes a year per 100 miles over 2015 to 2024, on 276 miles of road, against 5.8 for all interstates in Idaho. That ranks 1 of 2 interstates in Idaho and 103 of 172 interstate pages on this site. FARS records crashes, not traffic, so this is crashes per mile of road, not per vehicle.
Other roads in Idaho with a page
All fatal crashes in Idaho, with every road ranked.
Where the I-84 numbers come from
Counted from NHTSA's Fatality Analysis Reporting System, 2024 Annual Report File: every fatal crash whose road NHTSA filed as I-84 in Idaho (filed under 3 spellings, such as "I-84", "I-84 US-26", "I-84 W"). Ramps, frontage and service roads are left out. Where two routes share a road, NHTSA files each crash under one of them, so a shared stretch counts on one route only. A fatal crash is one in which someone died within 30 days. Totals in state and news reports for a road usually differ: they include ramps and frontage roads, or count from preliminary reports. The full method.