DeKalb County is a county in Missouri, United States, part of the St. Joseph metropolitan area, in the northwestern part of the state. It had a population of 11,029 at the 2020 census and covers 426 square miles (1,103 km2) centred near 39°54′N 94°24′W.
Maysville is the county seat, and its postal code is 64469. The county has six cities and two villages, plus several unincorporated communities, organised across nine civil townships. DeKalb County is in the Central time zone.
Towns & Villages in DeKalb County
DeKalb County has eight incorporated places — six cities and two villages — plus a handful of unincorporated communities that appear on older gazetteers but never organised a government. Cameron, the county’s largest city, straddles the DeKalb–Clinton county line; most of its population and its post office sit on the Clinton County side, so it is listed here as a place with a footprint in DeKalb County rather than a wholly DeKalb city.
| Place | Type | Pop. | ZIP |
|---|---|---|---|
| Maysville | City · seat | — | 64469 |
| Cameron | City | — | — |
| Stewartsville | City | — | 64490 |
| Osborn | City | — | 64474 |
| Union Star | City | — | 64494 |
| Clarksdale | City | — | 64430 |
| Amity | Village | — | 64422 |
| Weatherby | Village | — | 64497 |
| Alta Vista | Unincorp. | — | — |
| Fairport | Unincorp. | — | — |
| Santa Rosa | Unincorp. | — | — |
| Fordham | Unincorp. | — | — |
| Oak | Unincorp. | — | — |
| Orchid | Unincorp. | — | — |
| Winslow | Unincorp. | — | — |
| Wood | Unincorp. | — | — |
Townships
DeKalb County is divided into nine civil townships: Adams, Camden, Colfax, Dallas, Grand River, Grant, Polk, Sherman and Washington. Individual township population figures are not published in the sources checked for this profile, so populations are omitted below rather than estimated.
| Township | Pop. (2020) | Main settlements |
|---|---|---|
| Adams | — | — |
| Camden | — | — |
| Colfax | — | — |
| Dallas | — | — |
| Grand River | — | — |
| Grant | — | — |
| Polk | — | — |
| Sherman | — | — |
| Washington | — | — |
ZIP Codes
- 64469 — Maysville (also serves the surrounding rural townships)
- 64490 — Stewartsville
- 64494 — Union Star
- 64474 — Osborn
- 64430 — Clarksdale
- 64497 — Weatherby
- 64422 — Amity
Cameron uses a Clinton County post office and ZIP code because its downtown and city hall sit on that side of the county line. The unincorporated communities of Alta Vista, Fairport, Santa Rosa, Fordham, Oak, Orchid, Winslow and Wood have no ZIP code of their own; mail there is delivered under the nearest incorporated town’s code.
Geography
DeKalb County lies in the till plains of northwestern Missouri, a landscape of gently rolling hills used mostly for corn, soybeans and cattle pasture. Standing water is limited to about 4.5 square miles of the county’s total, roughly one percent, split among small lakes, farm ponds and streams draining generally toward the Missouri and Platte river basins.
DeKalb County borders Gentry County to the north, Daviess County to the east, Caldwell County to the southeast, Clinton County to the south, Buchanan County to the southwest and Andrew County to the west. See Gentry County, Daviess County, Caldwell County, Clinton County, Buchanan County and Andrew County.
Demographics
DeKalb County had a population of 11,029 at the 2020 census, a density of about 26 people per square mile. Cameron and Maysville are the county’s two largest population centers, with Cameron’s DeKalb County footprint smaller than its Clinton County side. Missouri’s statewide 2023 median household income is $68,545; DeKalb County, a mostly rural county without a large employment base of its own, typically runs below that figure, similar to its farming neighbors in the region.
Economy & Local Life
Agriculture — row crops, cattle and hog operations — remains the backbone of DeKalb County’s economy, supplemented by commuting to jobs in Cameron and St. Joseph. Cameron’s economy benefits from its position at the junction of Interstate 35 and U.S. Route 36, which has drawn truck-stop, warehousing and light-industrial development to the area. Maysville, the county seat, centers on county government, schools and farm-service businesses.
History
DeKalb County was organized on February 25, 1845, from parts of Clinton County, and was named for Johann de Kalb, a German-born major general who served under George Washington in the Revolutionary War and was killed at the Battle of Camden in 1780. The county seat was established at Maysville, which grew up around the county courthouse. Cameron, founded in the 1850s along the Hannibal & St. Joseph Railroad, developed into the county’s commercial hub once the rail line and later Interstate 35 crossed the area.
Getting There
Interstate 35 crosses the county north–south through Cameron, and U.S. Routes 36 and 69 both pass through the county, along with several state routes connecting the smaller towns.
- Cameron — 0 miles (within the county)
- St. Joseph — about 30 miles west
- Kansas City — about 55 miles south
- Chillicothe — about 35 miles east
The nearest commercial airport is Kansas City International Airport, roughly an hour’s drive south of Cameron.
Frequently Asked Questions
Where is DeKalb County, Missouri?
DeKalb County sits in the northwestern part of Missouri, part of the St. Joseph metropolitan area, along the Interstate 35 corridor between St. Joseph and Cameron.
What is the population of DeKalb County?
DeKalb County had a population of 11,029 at the 2020 census.
How big is DeKalb County?
The county covers 426 square miles (1,103 km2), of which about 421 square miles is land.
What is the DeKalb County seat?
Maysville is the county seat.
How many towns are in DeKalb County?
DeKalb County has six cities and two villages, plus several unincorporated communities.
What ZIP codes are in DeKalb County?
DeKalb County’s ZIP codes include 64469 (Maysville), 64490 (Stewartsville), 64494 (Union Star), 64474 (Osborn), 64430 (Clarksdale), 64497 (Weatherby) and 64422 (Amity).
Is Cameron in DeKalb County?
Part of Cameron, the county’s largest city, lies in DeKalb County, but most of the city and its post office are across the line in Clinton County.
More counties in this state: Towns and villages in Missouri.