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US Route 18
Fatal crashes 2015–2024 53Deaths 65Counties 10Latest 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.
Between 2015 and 2024, FARS records 53 fatal crashes on US Route 18 in South Dakota, with 65 deaths.
That is 4.5% of the 1,174 fatal crashes in South Dakota over the same years. The ten-year crash count was about level between 2005–2014 (54) and 2015–2024 (53).
The crashes were concentrated in Oglala Lakota County (23), Fall River County (12) and Lincoln County (4) and 7 other counties.
45.3% of the crashes had a driver reported as drinking (South Dakota: 34.9%) and 28.3% had a speeding-related driver (26.6%); pedestrians were 18.5% and motorcyclists 7.7% 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 South Dakota
| Measure | US Route 18 | South Dakota |
|---|---|---|
| Fatal crashes, 2015–2024 | 53 | 1,174 |
| Deaths, 2015–2024 | 65 | 1,323 |
| Deaths per fatal crash | 1.2 | 1.1 |
| Share of state fatal crashes | 4.5% | 100% |
| Change vs previous ten years | -2% | -8% |
Factor shares
Counties along the route
| # | County | Fatal crashes on US-18 | Share of route | County total, all roads |
|---|---|---|---|---|
| 1 | Oglala Lakota County | 23 | 43% | 55 |
| 2 | Fall River County | 12 | 23% | 21 |
| 3 | Lincoln County | 4 | 8% | 50 |
| 4 | Tripp County | 4 | 8% | 11 |
| 5 | Bennett County | 3 | 6% | 8 |
| 6 | Gregory County | 3 | 6% | 8 |
| 7 | Douglas County | 1 | 2% | 4 |
| 8 | Hutchinson County | 1 | 2% | 18 |
| 9 | Lawrence County | 1 | 2% | 75 |
| 10 | Turner County | 1 | 2% | 18 |
Hour of day
Share of fatal crashes on US Route 18 beginning in each hour, 2015–2024; tick marks the South Dakota share for all roads.
Where along the route
| Mile marker range | Fatal crashes | Share |
|---|---|---|
| Mile 100–105 | 7 | 13% |
| Mile 105–110 | 6 | 11% |
| Mile 20–25 | 3 | 6% |
| Mile 95–100 | 3 | 6% |
| Mile 60–65 | 2 | 4% |
| Mile 70–75 | 2 | 4% |
Five-mile bins by FARS milepoint, the six with the most fatal crashes; 96.2% 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 South Dakota
- Interstate 90 112
- Interstate 29 51
- US Route 14 34
- US Route 212 29
- US Route 12 26
- State Route 44 26
- US Route 16 24
- State Route 34 24
All routes and counties in South Dakota
Questions and answers
How many fatal crashes have there been on US Route 18 in South Dakota?
53 fatal crashes with 65 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 18 had the most fatal crashes?
Oglala Lakota County (23), Fall River County (12), Lincoln County (4), Tripp County (4) and Bennett County (3).
What share of crashes on US Route 18 involved alcohol or speeding?
45.3% had a driver reported as drinking and 28.3% a speeding-related driver, against 34.9% and 26.6% for all fatal crashes in South Dakota.
When do fatal crashes happen on US Route 18?
56.6% 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.