Audrain County is a county in Missouri, United States, in the north-central part of the state between the Mississippi and Missouri rivers. It had a population of 24,962 at the 2020 census and covers 692 square miles (1,790 km2) of land centred near 39°13′N 91°50′W.
Mexico is the county seat, and its postal code is 65265. The county has 5 incorporated cities, 4 villages, and several unincorporated communities spread across 8 civil townships. Audrain County is in the Central time zone; its FIPS code is 29007.
Towns & Villages in Audrain County
Audrain County has nine incorporated places and a handful of unincorporated communities. Mexico, the county seat, is by far the largest, home to roughly two-thirds of the county’s residents. The table below lists incorporated places (City, Village) and long-standing unincorporated communities (Unincorp.), grouped by the township each falls in.
| Place | Type | Township | Pop. | ZIP |
|---|---|---|---|---|
| Mexico | City · seat | Salt River | 11,469 | 65265 |
| Vandalia | City | Prairie | 3,553 | 63382 |
| Laddonia | City | Loutre | — | 63352 |
| Farber | City | Cuivre | — | 63345 |
| Rush Hill | Village | Loutre | — | 65280 |
| Martinsburg | Village | Loutre | — | 65264 |
| Vandiver | Village | Salt River | — | 65265 |
| Benton City | Village | South Fork | — | 65232 |
| Thompson | Unincorp. | Wilson | — | 65285 |
| Rowena | Unincorp. | Linn | — | — |
| Molino | Unincorp. | Saling | — | — |
| Saling | Unincorp. | Saling | — | — |
| Champ | Unincorp. | Cuivre | — | — |
| Hollensville | Unincorp. | Wilson | — | — |
| Skinner | Unincorp. | South Fork | — | — |
| Worcester | Unincorp. | Loutre | — | — |
A ninth incorporated city, Centralia, sits mostly across the line in neighboring Boone County and is not counted among Audrain’s own places. Three names from older listings — Bassinger Corner, Culiver, Larrabee, Rices Corner, and Scotts Corner — could not be independently verified against current gazetteer or Census sources and are omitted here; see notes.
Townships
| Township | Pop. (2020) | Main settlements |
|---|---|---|
| Salt River | — | Mexico, Vandiver |
| Prairie | — | Vandalia |
| Loutre | — | Laddonia, Rush Hill, Martinsburg, Worcester |
| Wilson | — | Thompson, Hollensville |
| Cuivre | — | Farber, Champ |
| South Fork | — | Benton City, Skinner |
| Saling | — | Saling, Molino |
| Linn | — | Rowena |
ZIP Codes
- 65265 — Mexico (also serves Vandiver)
- 63382 — Vandalia
- 63352 — Laddonia
- 63345 — Farber
- 65280 — Rush Hill
- 65264 — Martinsburg
- 65232 — Benton City
- 65285 — Thompson
Smaller unincorporated communities such as Rowena, Molino, Saling, Champ, Hollensville, Skinner, and Worcester use the ZIP code of their nearest post office town rather than a code of their own.
Geography
Audrain County lies on the rolling prairie of north-central Missouri, drained by tributaries of the Salt River and the Cuivre River. The terrain is gently rolling farmland with no large natural lakes; Mark Twain Lake sits just across the border to the east. The county borders Monroe County to the north, Ralls County to the northeast, Pike County to the east, Montgomery County to the southeast, Callaway County to the south, Boone County to the southwest, and Randolph County to the northwest.
Demographics
Audrain County had 24,962 residents at the 2020 census. Mexico and Vandalia together account for more than 60 percent of the county’s population, with the balance spread across the six smaller villages and unincorporated communities. Median household income in the county runs below the Missouri median of $68,545, reflecting the county’s largely rural, agricultural economic base. Population density is roughly 36 people per square mile, well below the statewide average.
Economy & Local Life
Agriculture, particularly corn, soybeans, and cattle, anchors the county’s rural economy, while Mexico serves as its commercial and institutional hub. Mexico is home to A.T. Still University’s Missouri campus (Kirksville College of Osteopathic Medicine’s satellite) and has a long history in the fire-brick and clay-products industry that earned it the nickname “Firebrick Capital of the World” in the 20th century. The Audrain County Fair, held in Mexico each summer, remains the county’s largest annual community event.
History
Audrain County was organized on December 17, 1836, from parts of Ralls and Callaway Counties, and named for Colonel James H. Audrain, a state legislator who died the year before the county’s creation and never lived to see it named for him. During the Civil War the county was divided in sentiment, and Union troops under Ulysses S. Grant passed through briefly in 1861. Mexico’s clay-brick industry, drawing on local fire-clay deposits, grew into a major regional employer through the late 1800s and early 1900s.
Getting There
U.S. Route 54 crosses the county north–south through Mexico, and Missouri Routes 15, 19, 22, and 151 connect the smaller towns. Approximate distances from Mexico:
- Columbia — 30 miles southwest
- Hannibal — 35 miles northeast
- Jefferson City — 45 miles south
- St. Louis — 100 miles east
The nearest commercial airport is Columbia Regional Airport (COU), about 35 miles southwest of Mexico.
Frequently Asked Questions
Where is Audrain County?
It is in north-central Missouri, between the Mississippi and Missouri rivers, roughly 100 miles northwest of St. Louis.
What is the population of Audrain County?
24,962 people, according to the 2020 census.
How big is Audrain County?
692 square miles (1,790 km2) of land area.
What is the county seat of Audrain County?
Mexico is the county seat.
How many towns are in Audrain County?
Nine incorporated cities and villages, plus several unincorporated communities.
What ZIP codes are in Audrain County?
Eight ZIP codes, led by 65265 for Mexico, plus 63382, 63352, 63345, 65280, 65264, 65232, and 65285.
What is Mexico, Missouri known for?
Its historic fire-brick and clay-products industry, which once earned it the nickname “Firebrick Capital of the World.”
More counties in this state: Towns and villages in Missouri.