Jefferson is a city in Union County, South Dakota, United States. The population was 475 at the 2020 census. It is part of the Sioux City, IA-NE-SD Metropolitan Statistical Area. Jefferson was founded in 1859. Every year the citizens of Jefferson and surrounding area celebrate the founding of Jefferson during "Jefferson Days", a festival that includes a movie in the park, a car show, fireworks and parade. The city has the name of President Thomas Jefferson.

From Wikipedia, licensed CC BY-SA 4.0 · facts via Wikidata (CC0)

Town numbers

ZIP code57038

Area code605

Living in Jefferson

Housing in Jefferson

$118K Median sale price · Redfin, February 2026

The median sale price was $118,000 in February 2026.

Zillow Home Value Index · Redfin Data CenterHousing market →

Safety in Jefferson

—

Not graded

Jefferson has fewer than 1,000 residents. At that size one or two incidents swing the numbers so much that a grade wouldn't be fair, so we show the counts instead.

Violent0

Property3

Reported in 20243

FBI crime data, 2024 · crimes reported to policeCrime & safety →

Work & commute in Jefferson

Full picture →

Most working residents leave Jefferson for work: only 1% work in town. The top destinations are North Sioux City (20%), Sioux City (15%) and Dakota Dunes (15%). Half commute less than 9 miles.

North Sioux City

20%

Sioux City, IA

15%

Dakota Dunes

15%

Sioux Falls

11%

1%Work in townlive and work in Jefferson 9 miWhere do people commute?the commute map 22Jobs based herea commuter town

Census LEHD 2023 · ACSWork & commute in Jefferson →

Health in Jefferson

A⁻

Health Grade A−

Healthier than 76% of U.S. towns on seven CDC estimates.

Compared with South Dakota

≈Just like South Dakota

No difference on any of 26 measures is outside the margin of error.

Conditions all close Habits all close Care all close Mind all close

BetterToo close to callWorse

What stands out

Nothing stands out: Jefferson tracks South Dakota closely.

Care nearby

St. Lukes Regional Medical CenterSioux City · 10.1 mi · ER

Horizon Health - Elk PointElk Point · 8.2 mi · sliding-scale fees

Primary careNo shortage

DentalNo shortage

Mental healthShortage · county-wide

CDC PLACES 2025 · modeled estimates for adults · CDC's estimate for Jefferson · CMS · HRSAHealth in Jefferson →

Natural hazards in Jefferson

Very high

Expected storm and flood damage is higher than in 82% of U.S. communities.

🌊 Inland flooding🌪️ Tornadoes

0Does Jefferson flood?no paid flood claims on record 4Disasters that paid out herefederal disasters sent FEMA money to Jefferson

FEMA National Risk Index December 2025 · OpenFEMANatural hazards in Jefferson →

Climate in Jefferson

Full climate →

Jefferson has cold, snowy winters and warm summers. A typical July afternoon reaches 86°, a January night drops to 10°, and about 36 inches of snow falls in a normal winter.

32° / 13°Winter

60° / 37°Spring

84° / 61°Summer

62° / 38°Fall