Bon Homme is a county in South Dakota, United States, along the Missouri River in the southeastern part of the state. It had a population of 7,003 at the 2020 census and covers 582 square miles (1,510 km2), of which 564 square miles (1,460 km2) is land, centred near 42°59′N 97°53′W.
Tyndall is the county seat, and its postal code is 57066. The county has four incorporated cities, one incorporated town, two census-designated places and two unincorporated communities. Bon Homme County sits in the Central time zone.
Towns & Villages in Bon Homme County
Nine named places appear across Bon Homme County’s cities, town, census-designated places and unincorporated communities. Type key: City = incorporated city, Town = incorporated town, CDP = census-designated place (unincorporated but federally recognized for census purposes), Unincorp. = unincorporated community with no formal boundary.
| Place | Type | Pop. | ZIP |
|---|---|---|---|
| Tyndall | City · seat | 1,057 | 57066 |
| Springfield | City | 1,914 | 57062 |
| Scotland | City | 785 | 57059 |
| Avon | City | 586 | 57315 |
| Tabor | Town | — | — |
| Running Water | CDP | — | — |
| Bon Homme Colony | CDP | — | — |
| Kingsburg | Unincorp. | — | — |
| Perkins | Unincorp. | — | — |
Springfield’s 2020 population of 1,914 residents includes the population held at the Mike Durfee State Prison, a state medium-security men’s facility on the site of the former Southern State Normal School; that institutional population makes Springfield larger on paper than the county seat, Tyndall.
ZIP Codes
- 57066 — Tyndall
- 57062 — Springfield
- 57059 — Scotland
- 57315 — Avon
Tabor and the county’s unincorporated communities are served by the ZIP code of their nearest post-office town rather than a code of their own; this page does not publish an unverified figure for them.
Geography
Bon Homme County occupies low, rolling hills that step down toward the Missouri River, which forms most of the county’s southern border. Most of the land is farmed for corn, soybeans and small grains. The county’s highest point, near 1,883 feet (574 m) above sea level, is in the northwest corner.
Bon Homme County borders Hutchinson County to the north, Yankton County to the east, Knox County, Nebraska to the south across the Missouri River, and Charles Mix County to the west.
Demographics
Bon Homme County had 7,003 residents at the 2020 census. Springfield (1,914) and Tyndall (1,057) are its two largest communities. The county’s median household income runs below the South Dakota median of $71,810, reflecting its farm-dependent, largely rural economy. Population density is about 12 people per square mile of land.
Economy & Local Life
Agriculture anchors the county economy — row-crop and livestock farming dominate outside the towns. The Mike Durfee State Prison in Springfield is one of the county’s largest single employers, alongside Avera Tyndall Medical Center and the local school districts. Tabor, settled by Czech immigrants in the 1870s, hosts an annual Czech Days festival each June that draws visitors from across the region.
History
Bon Homme County was organized on April 5, 1862, making it one of the oldest organized counties in what is now South Dakota. Its name comes from Bon Homme Island in the Missouri River, named by explorers William Clark and Meriwether Lewis in 1804 — “bon homme” is French for “good man.” The county seat began at the river village of Bon Homme and moved to Tyndall in 1885.
Getting There
South Dakota Highways 25, 37, 46, 50 and 52 cross the county, connecting its towns to Interstate 29 to the east.
- Yankton, SD — 20 miles east
- Mitchell, SD — 35 miles north
- Sioux Falls, SD — 75 miles east
- Norfolk, NE — 55 miles south
The nearest commercial airport is Sioux Falls Regional Airport, about 75 miles east of Tyndall.
Frequently Asked Questions
Where is Bon Homme County?
It is in southeastern South Dakota, along the Missouri River, bordering Nebraska to the south.
What is the population of Bon Homme County?
7,003 people, per the 2020 census.
How big is Bon Homme County?
582 square miles (1,510 km2), including 18 square miles of water.
What is the county seat of Bon Homme County?
Tyndall is the county seat.
How many towns are in Bon Homme County?
Four cities (Tyndall, Springfield, Scotland, Avon), one town (Tabor), two census-designated places and two unincorporated communities.
What ZIP codes are in Bon Homme County?
57066 (Tyndall), 57062 (Springfield), 57059 (Scotland) and 57315 (Avon).
Why is Springfield’s population larger than the county seat’s?
Springfield’s 2020 count includes the resident population of the Mike Durfee State Prison, a state facility housing over a thousand inmates.
More counties in this state: Towns and villages in South Dakota.