Sioux County, Iowa: fatal crash statistics

Counties of Iowa by year (CSV)Cite this page

FARS records 3 deaths in 1 or 2 fatal crashes in Sioux County in 2024.

FARS records 37 deaths in 34 fatal crashes in the county from 2015 to 2024.

From 2015 to 2024 the rate is 10.4 deaths for each 100,000 residents in a year.

The rate of Iowa in the same years is 11.0.

By deaths from 2015 to 2024, Sioux County was number 24 of 99 counties of Iowa.

Deaths in Sioux County fell by 24.5% between the ten years 2005 to 2014 (49) and the ten years 2015 to 2024 (37).

In the counties of Iowa the deaths fell by 10.1% between the same years.

From 2015 to 2024, 94.1% of the fatal crashes in Sioux County with a known setting were rural, against 71.5% in Iowa.

To qualify as a FARS case, the crash had to involve a motor vehicle traveling on a trafficway customarily open to the public and must have resulted in the death of a motorist or a non-motorist within 30 days of the crash.
The set of first files, known as the Annual Report File (ARF), is released following the crash year. The ARF is replaced about a year later with a final file, which contains additional cases or updates to cases that had become available after the ARF was released.
NHTSA's words. Source: NHTSA, Fatality Analysis Reporting System Analytical User's Manual, 1975-2024 (DOT HS 813 794, April 2026), copied on 2 Oct 2026.

This page rests on the FARS 2024 annual file. NHTSA released it on 1 Apr 2026. NHTSA can revise the counts in the final file. Release dates

Figure 1.Deaths in Sioux County by year, 2015 to 2024

1 or 2

Table 1 has the numbers. Go to the table

Since the last update: no figure of this county has a change on record.

Deaths and fatal crashes by year

Table 1.Sioux County: deaths and fatal crashes by year, 2015 to 2024
Year	Deaths	Fatal crashes	Crashes with a driver recorded as drinking
2024	3	1 or 2	0
2023	6	6	1 or 2
2022	8	6	0
2021	3	3	1 or 2
2020	3	3	0
2019	1 or 2	1 or 2	0
2018	1 or 2	1 or 2	1 or 2
2017	3	3	1 or 2
2016	4	4	1 or 2
2015	3	3	0
2015 to 2024	37	34	6

Each year from 1975

Figure 2.Deaths in Sioux County by year, 1975 to 2024

Tallest column: 12 (1990)2024: 3

The columns with a stronger shade are the years 2015 to 2024.

Table 2.Sioux County: deaths and fatal crashes by year, 1975 to 2024
Year	Deaths	Fatal crashes
2024	3	1 or 2
2023	6	6
2022	8	6
2021	3	3
2020	3	3
2019	1 or 2	1 or 2
2018	1 or 2	1 or 2
2017	3	3
2016	4	4
2015	3	3
2014	1 or 2	1 or 2
2013	1 or 2	1 or 2
2012	3	3
2011	1 or 2	1 or 2
2010	5	5
2009	7	6
2008	4	3
2007	8	6
2006	7	6
2005	10	10
2004	4	4
2003	8	8
2002	5	5
2001	1 or 2	1 or 2
2000	9	9
1999	4	4
1998	9	7
1997	6	6
1996	6	5
1995	6	4
1994	1 or 2	1 or 2
1993	4	4
1992	1 or 2	1 or 2
1991	7	7
1990	12	7
1989	5	4
1988	8	8
1987	5	5
1986	7	5
1985	5	4
1984	3	3
1983	3	3
1982	5	5
1981	4	4
1980	6	6
1979	6	6
1978	10	8
1977	9	6
1976	8	8
1975	7	5

Note: a count of 1 or 2 is written "1 or 2". A death is in FARS when it occurs in 30 days or less after the crash.

Rate for each 100,000 residents

Table 3.Sioux County beside Iowa and the United States: deaths for each 100,000 residents
Period	Sioux County	Iowa	United States
2024	8.2	11.0	11.5
2015 to 2024, in a year	10.4	11.0	11.8

Note: the rate divides the deaths in the county by its residents. Persons who do not live in the county are in the deaths, not in the residents.

Population: Census Bureau estimates, vintage 2025. Sioux County had 36,777 residents in 2024.

Factors that NHTSA records

Table 4.Sioux County: counts by recorded factor, 2015 to 2024
Factor	Count	Counted among	Share	Share in Iowa
A driver recorded as drinkingof 34 fatal crashes	6	34 fatal crashes	17.6%	25.4%
A speeding-related driverof 34 fatal crashes	6	34 fatal crashes	17.6%	20.2%
No restraint usedof 30 occupant deaths with restraint use known	16	30 occupant deathswith restraint use known	53.3%	48.1%
Pedestriansof 37 deaths	1 or 2	37 deaths	5.4%	7.1%
Bicyclistsof 37 deaths	1 or 2	37 deaths	2.7%	2.0%
Motorcyclistsof 37 deaths	1 or 2	37 deaths	5.4%	15.7%
On a rural roadof 34 fatal crashes with the condition reported	32	34 fatal crasheswith the condition reported	94.1%	71.5%
In the darkof 34 fatal crashes with the condition reported	15	34 fatal crasheswith the condition reported	44.1%	39.9%

Note: FARS records a driver as drinking when police reported alcohol involvement or a test of the driver was positive for alcohol. It is not NHTSA's alcohol-impaired measure, which uses a blood alcohol concentration of .08 g/dL or higher. One crash can be in two or more rows. NHTSA's definitions

Note that alcohol data is often missing. For that reason, this data element may under-count the actual number of drinking drivers.

NHTSA's words. Source: NHTSA, Fatality Analysis Reporting System Analytical User's Manual, 1975-2024 (DOT HS 813 794, April 2026), copied on 2 Oct 2026.

Weekday, time and road class

Table 5.Sioux County: fatal crashes by weekday and time of day, 2015 to 2024
Weekday	Midnight to 6 a.m.	6 a.m. to noon	Noon to 6 p.m.	6 p.m. to midnight	All
Sunday	1 or 2	1 or 2	0	1 or 2	6
Monday	0	1 or 2	4	1 or 2	7
Tuesday	0	1 or 2	1 or 2	4	7
Wednesday	1 or 2	1 or 2	1 or 2	1 or 2	4
Thursday	0	0	1 or 2	1 or 2	4
Friday	0	1 or 2	1 or 2	1 or 2	5
Saturday	1 or 2	0	0	0	1 or 2
All days	4	8	11	11	34

Note: a cell with a stronger shade has a larger count. The table has the fatal crashes with a known hour and weekday.

Table 6.Sioux County: fatal crashes by road function class, 2015 to 2024
Road function class	Fatal crashes	Share	Share in Iowa
Interstate	0	0.0%	11.0%
Other freeways and expressways	0	0.0%	0.1%
Other principal arterial	10	29.4%	29.3%
Minor arterial	4	11.8%	17.4%
Major collector	7	20.6%	20.0%
Minor collector	6	17.6%	5.7%
Local	7	20.6%	16.4%
Not reported	0	n/a	n/a

Note: the classes are those of the Federal Highway Administration. The shares are of the crashes with a reported class. Road function classes

Light condition and weather

Table 7.Sioux County: fatal crashes by light condition, 2015 to 2024
Light condition	Fatal crashes
Daylight	16
Dark, not lighted	11
Dark, lighted	3
Dawn	1 or 2
Dusk	1 or 2
Dark, lighting unknown	1 or 2
Other or unknown	0

Table 8.Sioux County: fatal crashes by weather, 2015 to 2024
Weather	Fatal crashes
Clear	20
Cloudy	8
Rain	1 or 2
Snow, sleet or freezing rain	1 or 2
Fog, smog or smoke	1 or 2
Crosswinds or blowing sand/snow	1 or 2
Other or not reported	0

Routes in the county

Table 9.Signed routes in Sioux County that have a page: fatal crashes, 2015 to 2024
Route	Type	In Sioux	In all of Iowa
US Route 18	US highway	4	41
US Route 75	US highway	5	25

Note: the table has each route with a page that has a fatal crash in the county, in name order. Local streets and county roads have no page. Their crashes are in the county totals. All routes in Iowa

Adjacent counties

These lists are for navigation. They are in name order.

Figure 3.Sioux County on the county map of Iowa

Deaths for each 100,000 residents in a year, 2015 to 2024

Fewer than 1015 counties
10 to 14.941 counties
15 to 19.924 counties
20 to 29.915 counties
30 or more4 counties
Sioux County: 10.4

The limits of the classes are the same for every state. A county with few residents can show a high rate from few deaths. A class is not a judgement of a county. The full map and the table of counties of Iowa

Table 10.Counties that share a boundary line with Sioux County
County	State	Deaths, 2024	Deaths, 2015 to 2024	For each 100,000 residents in a year
Lyon County	Iowa	1 or 2	15	12.5
O'Brien County	Iowa	1 or 2	20	14.3
Plymouth County	Iowa	6	43	16.9
Lincoln County	South Dakota	8	56	8.8
Union County	South Dakota	1 or 2	18	11.1

Source of the list: Census Bureau county adjacency file, 2026 edition.

Counties of similar population

These counties of Iowa have a population nearest to that of Sioux County. The list is for navigation and is in name order. The number is the deaths from 2015 to 2024.

Official channels

NHTSA Fatality and Injury Reporting System Tool (FIRST)NHTSA's query tool for FARS counts.
NHTSA FARS EncyclopediaNHTSA's tables of FARS data.
Iowa Governor's Traffic Safety BureauThe highway safety office of Iowa.

These links go to the sites of the agencies. They were checked on 2 Oct 2026.

Cite this page

Fatal Roads. Sioux County, Iowa: fatal crash statistics. https://fatalroads.com/county/ia/sioux/. Source: National Highway Traffic Safety Administration, Fatality Analysis Reporting System, FARS 2024 annual file. Data to 31 Dec 2024.

The address of this page does not change.

Source of the figures

Counts: National Highway Traffic Safety Administration, Fatality Analysis Reporting System, national files of 1975 to 2024. The factors use the vehicle and person files from 2015. Residents: Census Bureau, Population Estimates Program, vintage 2025. Map: Census Bureau cartographic boundary file, 2021 edition. Data to 31 Dec 2024. The figures are totals. No page of this site is about one crash or one person.

How the figures are made. Data sources and licences. Corrections.

Questions

How many deaths did FARS record in Sioux in the ten years before 2015?

FARS records 49 deaths in Sioux County from 2005 to 2014. It records 37 deaths from 2015 to 2024.

What was the rate of Sioux in 2024?

The rate of Sioux County in 2024 was 8.2 deaths for each 100,000 residents. The rate of Iowa was 11.0. The rate of the United States was 11.5.

How many fatal crashes in Sioux had a driver recorded as drinking?

FARS records a driver as drinking in 6 of 34 fatal crashes from 2015 to 2024. This count is not NHTSA's alcohol-impaired measure. NHTSA says that alcohol data is often missing, so the count may be too low.

How many fatal crashes did FARS record on signed routes in Sioux?

FARS records 4 fatal crashes on US Route 18 in the county from 2015 to 2024. FARS records 5 fatal crashes on US Route 75 in the county from 2015 to 2024.