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US Route 421
Fatal crashes 2015–2024 24Deaths 26Counties 2Latest data year 2024
FARS data are based on police crash reports and other sources; the drunk-driving measure is based on the highest BAC of any driver in the crash. Latest data year: 2024. The route is the trafficway recorded for each crash (FARS TWAY_ID); the same route number in another state has its own page.
US Route 421 in Tennessee was the trafficway in 24 fatal crashes between 2015 and 2024, in which 26 people died.
That is 0.2% of the 10,680 fatal crashes in Tennessee over the same years. The ten-year crash count rose 700% from 3 in 2005–2014 to 24 in 2015–2024.
The crashes were concentrated in Sullivan County (13) and Johnson County (11).
20.8% of the crashes had a driver reported as drinking (Tennessee: 24.5%) and 16.7% had a speeding-related driver (16.5%); pedestrians were 7.7% and motorcyclists 50.0% of those killed.
Fatal crashes per year
Route identification in FARS is consistent from 2000; earlier years are not shown. Shaded band: the ten-year window used for the shares below.
Compared with all fatal crashes in Tennessee
| Measure | US Route 421 | Tennessee |
|---|---|---|
| Fatal crashes, 2015–2024 | 24 | 10,680 |
| Deaths, 2015–2024 | 26 | 11,576 |
| Deaths per fatal crash | 1.1 | 1.1 |
| Share of state fatal crashes | 0.2% | 100% |
| Change vs previous ten years | +700% | +8% |
Factor shares
Counties along the route
| # | County | Fatal crashes on US-421 | Share of route | County total, all roads |
|---|---|---|---|---|
| 1 | Sullivan County | 13 | 54% | 189 |
| 2 | Johnson County | 11 | 46% | 41 |
Hour of day
Share of fatal crashes on US Route 421 beginning in each hour, 2015–2024; tick marks the Tennessee share for all roads.
Where along the route
| Mile marker range | Fatal crashes | Share |
|---|---|---|
| Mile 20–25 | 8 | 33% |
| Mile 15–20 | 5 | 21% |
| Mile 25–30 | 3 | 13% |
| Mile 30–35 | 3 | 13% |
| Mile 0–5 | 2 | 8% |
| Mile 5–10 | 2 | 8% |
Five-mile bins by FARS milepoint, the six with the most fatal crashes; 100% of crashes on the route have a milepoint. Milepoints are as recorded by the state and can restart at county or district lines.
Other routes in Tennessee
- Interstate 40 588
- Interstate 24 320
- US Route 70 214
- US Route 64 168
- Interstate 75 165
- US Route 41 157
- Interstate 65 148
- US Route 51 137
- US Route 11 112
- US Route 41A 98
- Interstate 240 95
- US Route 11E 95
All routes and counties in Tennessee
Questions and answers
How many fatal crashes have there been on US Route 421 in Tennessee?
24 fatal crashes with 26 deaths over 2015–2024, per NHTSA's FARS. The route is the trafficway recorded for the crash; the same numbered route in another state has its own page.
Which counties along US Route 421 had the most fatal crashes?
Sullivan County (13) and Johnson County (11).
What share of crashes on US Route 421 involved alcohol or speeding?
20.8% had a driver reported as drinking and 16.7% a speeding-related driver, against 24.5% and 16.5% for all fatal crashes in Tennessee.
When do fatal crashes happen on US Route 421?
20.8% of the crashes were between 6pm and 6am. The hour chart on this page shows the full distribution.
Provenance
Source: NHTSA Fatality Analysis Reporting System, annual national CSV files 2000–2024 (accident, vehicle and person tables), public domain. Route pages are built for signed Interstate, US and state routes with at least 20 fatal crashes in 2015–2024. Data through 31 Dec 2024; generated 30 Sep 2026. See methodology and corrections.