Fatal Crash Data

Fatal crashes in Jefferson County, Colorado

In 2024, 54 people died in 52 fatal crashes in Jefferson County, 14.9% more than in 2023. From 2015 to 2024 the county recorded 450 fatal crashes and 478 deaths, the 6th most of any county in Colorado.

9.3 deaths per 100,000 residents, against 11.6 across Colorado in 2024; 8.3 against 11.4 a year over 2015 to 2024. Population 578,533, Census Bureau estimate. All fatal crashes in Colorado.

Deaths in Jefferson County by year

2040201620182020202220242015: 552024: 54
YearFatal crashesDeaths
20245254
20234747
20224949
20215052
20204143
20194551
20183638
20173541
20164548
20155055

Source: NHTSA Fatality Analysis Reporting System (FARS), 2024 Annual Report File (released April 2026, subject to revision). How we count

The deadliest roads in Jefferson County

State Highway 121 had the most fatal crashes of any numbered road in Jefferson County from 2015 to 2024: 56, with 58 deaths. The 12 roads listed held 58% of all fatal crashes in Jefferson County from 2015 to 2024; 1 is an interstate, 3 US routes, 8 state highways. Interstate, US and state routes with 5 or more fatal crashes in the county; county roads and city streets are in the county's total but not listed.

RoadFatal crashesDeaths2022 to 2024
1State Highway 121565816
2US 636377
3I-70313911
4US 40303012
5State Highway 391272811no page
6US 28526318
7State Highway 9516166
8State Highway 7212156no page
9State Highway 47010115
10State Highway 74781no page
11State Highway 8662no page
12State Highway 93552no page

Cities NHTSA filed, with their fatal crashes from 2015 to 2024: Lakewood 145, Arvada 40, Westminster 29, Wheat Ridge 23, Golden 17. The city is not filed for crashes outside a city.

Source: NHTSA Fatality Analysis Reporting System (FARS), 2024 Annual Report File (released April 2026, subject to revision). How we count

When fatal crashes happen in Jefferson County

The heaviest slot is Sunday, 8 pm to midnight, with 24 fatal crashes from 2015 to 2024. The worst hour is 8 pm to 9 pm; the worst month is July.

Share of fatal crashes in Jefferson County by weekday and time of day, 2015 to 2024, in percent
Midnight to 44 to 8 am8 to noonNoon to 44 to 8 pm8 to midnight
Sun2.2 percent, 10 fatal crashes1.1 percent, 5 fatal crashes2.2 percent, 10 fatal crashes4.0 percent, 18 fatal crashes4.9 percent, 22 fatal crashes5.3 percent, 24 fatal crashes
Mon1.8 percent, 8 fatal crashes0.7 percent, 3 fatal crashes1.1 percent, 5 fatal crashes3.3 percent, 15 fatal crashes2.7 percent, 12 fatal crashes2.0 percent, 9 fatal crashes
Tue0.9 percent, 4 fatal crashes1.1 percent, 5 fatal crashes1.6 percent, 7 fatal crashes2.7 percent, 12 fatal crashes4.2 percent, 19 fatal crashes2.7 percent, 12 fatal crashes
Wed1.6 percent, 7 fatal crashes2.2 percent, 10 fatal crashes1.1 percent, 5 fatal crashes1.1 percent, 5 fatal crashes2.2 percent, 10 fatal crashes2.4 percent, 11 fatal crashes
Thu1.8 percent, 8 fatal crashes0.4 percent, 2 fatal crashes2.0 percent, 9 fatal crashes2.7 percent, 12 fatal crashes3.6 percent, 16 fatal crashes3.3 percent, 15 fatal crashes
Fri0.7 percent, 3 fatal crashes1.8 percent, 8 fatal crashes0.7 percent, 3 fatal crashes1.3 percent, 6 fatal crashes4.4 percent, 20 fatal crashes4.9 percent, 22 fatal crashes
Sat1.8 percent, 8 fatal crashes0.9 percent, 4 fatal crashes2.7 percent, 12 fatal crashes4.4 percent, 20 fatal crashes4.7 percent, 21 fatal crashes2.9 percent, 13 fatal crashes

By hour

By month

  • Jan5.6%
  • Feb5.3%
  • Mar6.9%
  • Apr7.8%
  • May9.6%
  • Jun9.8%
  • Jul12.7%
  • Aug10.4%
  • Sep10.7%
  • Oct8.4%
  • Nov4.9%
  • Dec8.0%

Source: NHTSA Fatality Analysis Reporting System (FARS), 2024 Annual Report File (released April 2026, subject to revision). How we count

What fatal crashes in Jefferson County first hit

The first harmful event was a collision with another vehicle in 36%; a fixed object such as a tree, pole or barrier in 25%, a pedestrian in 18%, a rollover in 12%.

First harmful eventFatal crashesShare
Collision with another vehicle16436%
Fixed object (tree, pole, barrier, ditch)11125%
Pedestrian8018%
Rollover5512%
Cyclist184.0%
Other184.0%
Parked vehicle40.9%
Not reported00.0%

Source: NHTSA Fatality Analysis Reporting System (FARS), 2024 Annual Report File (released April 2026, subject to revision). How we count

How fatal crashes in Jefferson County compare with Colorado

A drinking driver was recorded in 34% of fatal crashes in Jefferson County from 2015 to 2024, about the Colorado share; speeding in 37%, above the Colorado share of 35%; a hit-and-run in 6.7%, about the Colorado share; a driver recorded as distracted in 7.1%, below the Colorado share of 9.8%; 49% of passenger-vehicle occupants killed with belt use known were unbelted, below the Colorado share of 54%. Shares of fatal crashes from 2015 to 2024, against the share across all of Colorado. A share is only given over 20 crashes.

JeffersonColorado
On rural roads18%39%below the Colorado share
At or near an intersection35%32%above the Colorado share
In the dark, road unlit12%21%below the Colorado share
A drinking driver34%34%about the same as the Colorado share
Speeding37%35%above the Colorado share
A distracted driver (as recorded)7.1%9.8%below the Colorado share
Occupants killed unbelted49%54%below the Colorado share
Hit-and-run6.7%6.1%about the same as the Colorado share
A motorcycle involved31%21%above the Colorado share
Pedestrians among the dead18%14%above the Colorado 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 in Jefferson County

How many people died in car accidents in Jefferson County in 2024?
54 people died in 52 fatal crashes in Jefferson County, Colorado, in 2024, 14.9% more than in 2023. That is 9.3 deaths per 100,000 residents, against 11.6 across Colorado.
What is the deadliest road in Jefferson County?
State Highway 121 had the most fatal crashes of any numbered road in Jefferson County from 2015 to 2024: 56, with 58 deaths.
When do fatal crashes in Jefferson County happen most often?
The heaviest slot from 2015 to 2024 was Sunday, 8 pm to midnight, with 24 fatal crashes.
How many fatal crashes in Jefferson County involved a drinking driver?
154 of 450 fatal crashes in Jefferson County from 2015 to 2024 involved a driver NHTSA recorded as drinking, 34%, against 34% across Colorado.

Other counties in Colorado with a page

All fatal crashes in Colorado, with every county ranked.

Where the Jefferson County numbers come from

Counted from NHTSA's Fatality Analysis Reporting System, 2024 Annual Report File: every fatal crash NHTSA filed in Jefferson County (county code 59). A fatal crash is one in which someone died within 30 days. The rate per 100,000 uses the Census Bureau's population estimate for the county; it is the only figure here not counted from FARS. The full method.