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Mason County
Residents 12,543Deaths 2024 1–2Deaths 2015–2024 31Latest 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.
NHTSA's FARS file lists 31 people killed in 27 fatal crashes in Mason County, Illinois, between 2015 and 2024, fewer than three of them in 2024.
With 12,543 residents, that is 23.5 deaths per 100,000 people a year over the ten years, about 2.6 times the Illinois rate of 9.0 and above the national rate of 11.8.
The ten-year death toll rose 15% from 27 in 2005–2014 to 31 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): 37.0% against 27.2% for Illinois.
33% of the county's fatal crashes happened between 6am to noon, and Tuesday was the most common day (22%).
Trend since 1975
Ten-year total up 15% (27 in 2005–2014, 31 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 | Mason | Illinois | United States |
|---|---|---|---|
| Deaths per 100,000 residents a year, 2015–2024 | 23.5 | 9.0 | 11.8 |
| Deaths per 100,000 residents, 2024 | 15.9 | 9.3 | 11.5 |
| Deaths, 2015–2024 | 31 | 11,423 | 389,190 |
| Fatal crashes, 2015–2024 | 27 | 10,472 | 358,460 |
| Deaths per fatal crash | 1.1 | 1.1 | 1.1 |
| Change vs previous ten years | +15% | +8% | +7% |
| Crashes on rural roads | 96% | 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 12,543 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
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Fatal crashes in Mason County by weekday and hour, 2015–2024: darker cells are busier. 27 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 Mason
| # | Route | Type | In county | Fatal crashes | Deaths | Alcohol | Speeding |
|---|---|---|---|---|---|---|---|
| 1 | US Route 136 | US highway | 4 | 27 | 29 | 33% | 41% |
| 2 | State Route 78 | State highway | 3 | 23 | 25 | 30% | 30% |
| 3 | State Route 29 | State highway | 1 | 54 | 59 | 19% | 26% |
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 | 1–2 | 1–2 | 0 | — | IL 2024 |
| 2023 | 7 | 7 | 1–2 | 55.8 | IL 2023 |
| 2022 | 1–2 | 1–2 | 0 | — | IL 2022 |
| 2021 | 5 | 7 | 4 | 55.8 | IL 2021 |
| 2020 | 4 | 4 | 1–2 | 31.9 | IL 2020 |
| 2019 | 1–2 | 3 | 0 | 23.9 | IL 2019 |
| 2018 | 1–2 | 3 | 1–2 | 23.9 | IL 2018 |
| 2017 | 1–2 | 1–2 | 0 | — | IL 2017 |
| 2016 | 0 | 0 | 0 | — | IL 2016 |
| 2015 | 1–2 | 1–2 | 1–2 | — | 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 Mason County, Illinois?
fewer than three people died in fewer than three fatal crashes in 2024; 21 over 2020–2024 and 31 over 2015–2024, according to NHTSA's Fatality Analysis Reporting System.
How does Mason compare with Illinois?
23.5 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 Mason involved alcohol?
37.0% 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 37.0%.
Which roads in Mason see the most fatal crashes?
Among signed routes with a page on this site, US Route 136 (4 fatal crashes in the county, 2015–2024), State Route 78 (3 fatal crashes in the county, 2015–2024) and State Route 29 (1 fatal crashes in the county, 2015–2024).
When do fatal crashes happen in Mason?
Most often between 6am to noon (33% of crashes) and on Tuesdays (22%); 48.1% 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.