States › Illinois › St. Clair County
St. Clair County
Residents 251,149Deaths 2024 45Deaths 2015–2024 371Latest 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. Figures are aggregates from NHTSA's Fatality Analysis Reporting System; no individual crash is identified.
St. Clair County, Illinois, recorded 45 deaths in 40 fatal crashes in 2024, the latest FARS data year, and 371 deaths in 346 fatal crashes over 2015–2024.
With 251,149 residents, that is 14.4 deaths per 100,000 people a year over the ten years, 60% higher than the Illinois rate of 9.0 and above the national rate of 11.8.
The ten-year death toll rose 5% from 352 in 2005–2014 to 371 in 2015–2024.
Of the factors FARS records, the one that stands furthest above the state share here is alcohol (a driver reported as drinking): 32.9% against 27.2% for Illinois.
34% of the county's fatal crashes happened between 6pm to midnight, and Saturday was the most common day (19%).
Trend since 1975
Ten-year total up 5% (352 in 2005–2014, 371 in 2015–2024). The shaded band is the ten-year window used for rates and shares. County codes are matched to today's Census county list; a few historic code changes are merged.
Compared with Illinois and the nation
| Measure | St. Clair | Illinois | United States |
|---|---|---|---|
| Deaths per 100,000 residents a year, 2015–2024 | 14.4 | 9.0 | 11.8 |
| Deaths per 100,000 residents, 2024 | 17.9 | 9.3 | 11.5 |
| Deaths, 2015–2024 | 371 | 11,423 | 389,190 |
| Fatal crashes, 2015–2024 | 346 | 10,472 | 358,460 |
| Deaths per fatal crash | 1.1 | 1.1 | 1.1 |
| Change vs previous ten years | +5% | +8% | +7% |
| Crashes on rural roads | 16% | 34% | 43% |
Rates divide deaths by Census Bureau population estimates for each year (residents, not road users; through traffic on major routes raises the rate of small counties). Population 251,149 in 2024.
Factors
"Alcohol" counts crashes where police reported at least one driver as drinking (FARS DR_DRINK), not the BAC-based alcohol-impaired measure NHTSA publishes separately. "Speeding" counts crashes with a driver coded as racing, exceeding the limit or too fast for conditions. Details in the methodology. Factor pages: alcohol, speeding, pedestrians, motorcycles, unrestrained occupants.
Time of day and day of week
| 12am | 3am | 6am | 9am | 12pm | 3pm | 6pm | 9pm | |||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sun | ||||||||||||||||||||||||
| Mon | ||||||||||||||||||||||||
| Tue | ||||||||||||||||||||||||
| Wed | ||||||||||||||||||||||||
| Thu | ||||||||||||||||||||||||
| Fri | ||||||||||||||||||||||||
| Sat |
Fatal crashes in St. Clair County by weekday and hour, 2015–2024: darker cells are busier. 346 crashes with a known hour and weekday.
By weekday
Light condition
Road type
FHWA functional classes as coded in FARS (FUNC_SYS), share of fatal crashes with a reported class; tick marks the Illinois share. Interstates and other principal arterials carry the most traffic, so a high share there is expected. See what the road classes mean.
Weather
Routes with the most fatal crashes in St. Clair
| # | Route | Type | In county | Fatal crashes | Deaths | Alcohol | Speeding |
|---|---|---|---|---|---|---|---|
| 1 | Interstate 64 | Interstate | 31 | 58 | 62 | 26% | 35% |
| 2 | State Route 3 | State highway | 26 | 85 | 93 | 37% | 33% |
| 3 | State Route 161 | State highway | 19 | 27 | 30 | 26% | 22% |
| 4 | State Route 15 | State highway | 17 | 45 | 51 | 33% | 31% |
| 5 | Interstate 255 | Interstate | 16 | 31 | 32 | 19% | 32% |
| 6 | State Route 13 | State highway | 14 | 53 | 58 | 17% | 17% |
| 7 | State Route 157 | State highway | 12 | 25 | 25 | 24% | 32% |
| 8 | Interstate 55 | Interstate | 11 | 255 | 290 | 30% | 52% |
| 9 | US Route 50 | US highway | 10 | 55 | 68 | 18% | 27% |
| 10 | State Route 159 | State highway | 10 | 22 | 26 | 36% | 41% |
Signed routes (Interstate, US and state highways) that have a page on this site, ranked by fatal crashes in this county over 2015–2024; "fatal crashes" and "deaths" columns are the statewide totals for the route. Local streets and county roads are not listed.
By year, 2015–2024
| Year | Fatal crashes | Deaths | Drinking-driver crashes | Per 100,000 | |
|---|---|---|---|---|---|
| 2024 | 40 | 45 | 14 | 17.9 | IL 2024 |
| 2023 | 36 | 36 | 9 | 14.3 | IL 2023 |
| 2022 | 46 | 47 | 10 | 18.7 | IL 2022 |
| 2021 | 34 | 40 | 20 | 15.9 | IL 2021 |
| 2020 | 32 | 32 | 6 | 12.7 | IL 2020 |
| 2019 | 25 | 26 | 10 | 10.4 | IL 2019 |
| 2018 | 30 | 30 | 9 | 11.9 | IL 2018 |
| 2017 | 32 | 36 | 15 | 14.3 | IL 2017 |
| 2016 | 37 | 40 | 13 | 15.9 | IL 2016 |
| 2015 | 34 | 39 | 8 | 15.5 | IL 2015 |
Counts under three are shown as "1–2" (small-count rule). Per-100,000 uses the 2024 population for every year in this table; the ten-year rate above uses each year's estimate.
Questions and answers
How many people died in crashes in St. Clair County, Illinois?
45 people died in 40 fatal crashes in 2024; 200 over 2020–2024 and 371 over 2015–2024, according to NHTSA's Fatality Analysis Reporting System.
How does St. Clair compare with Illinois?
14.4 deaths per 100,000 residents a year over 2015–2024, against 9.0 for Illinois and 11.8 nationally. Rates use Census Bureau population estimates.
What share of fatal crashes in St. Clair involved alcohol?
32.9% of fatal crashes in 2015–2024 had at least one driver reported by police as drinking, against 27.2% in Illinois. The factor furthest above the state share was alcohol (a driver reported as drinking) at 32.9%.
Which roads in St. Clair see the most fatal crashes?
Among signed routes with a page on this site, Interstate 64 (31 fatal crashes in the county, 2015–2024), State Route 3 (26 fatal crashes in the county, 2015–2024) and State Route 161 (19 fatal crashes in the county, 2015–2024).
When do fatal crashes happen in St. Clair?
Most often between 6pm to midnight (34% of crashes) and on Saturdays (19%); 57.8% happened after dark.
Where does this data come from?
NHTSA's Fatality Analysis Reporting System annual files (1975–2024) and Census Bureau county population estimates. Figures are aggregates; no individual crash is identified. See the methodology page for definitions.
Provenance
Source: National Highway Traffic Safety Administration, Fatality Analysis Reporting System, annual national CSV files 1975–2024 (accident table for every year; vehicle and person tables for 2015–2024), public domain. Population: US Census Bureau, Population Estimates Program, county totals (vintages 2000–2010, 2010–2020 and 2020–2024). Data through 31 Dec 2024; page generated 30 Sep 2026. Processing errors are corrected at the next build; see corrections and sources.