Platte County, Missouri

Platte County is a county in Missouri, United States, on the northwest edge of the Kansas City metropolitan area. Kansas City International Airport sits inside the county, 15 miles northwest of downtown Kansas City. Platte County had a population of 106,718 at the 2020 census, an estimated 114,400 by 2025, and covers 420 square miles (1,100 km2) of land centred near 39°23′N 94°46′W.

Platte City is the county seat; its postal code is 64079. The county holds 15 cities (two of them, Kansas City and Smithville, mostly in neighboring counties), 4 incorporated villages, 1 census-designated place and 11 unincorporated communities, and it runs on Central Time.

Towns & Villages in Platte County

Platte County has 31 named places on record: 20 incorporated cities and villages, one census-designated place, and 11 unincorporated communities with no local government of their own. CDP stands for census designated place; Unincorp. covers crossroads and rural communities with no formal boundary.

Two places on this list straddle county lines. Smithville’s population figure above is citywide — most of the city sits in Clay County, with only its western edge reaching into Platte. Kansas City runs the same way: the vast majority of its 508,090 residents live in Jackson, Clay and Cass counties, and only the Northland neighborhoods around the airport and Zona Rosa fall inside Platte County. The earlier version of this page also listed “North Moor” as a separate community from Northmoor and repeated New Market twice; both were the same place counted twice, and several other names on the old list — Bean Lake Station, Breen Acres, Buxton, Haydite, Linkville, Milton, Northern Heights, Parkdale, Platte Gardens, Sadler, Sugar Lake and Tarrytown — do not appear in any current Census or Missouri gazetteer source and have been dropped.

ZIP Codes

• 64079 — Platte City (also serves Tracy)
• 64089 — Smithville
• 64018 — Camden Point
• 64439 — Dearborn
• 64444 — Edgerton
• 64028 — Farley
• 64163 — Ferrelview
• 64098 — Weston
• 64150 — Riverside
• 64151 — Northland communities: Houston Lake, Lake Waukomis, Northmoor and Platte Woods, plus part of Parkville
• 64152–64153 — Parkville and Weatherby Lake

Iatan, Ridgely, New Market and the county’s eleven unincorporated communities have no ZIP code of their own; mail there is delivered under the nearest incorporated town’s code.

Geography

Platte County occupies the southern end of the Platte Purchase, the block of land added to Missouri’s northwest corner in 1837. Of its 420 square miles of land, the county carries about 6.6 square miles of water, roughly 1.5 percent — the Missouri River forms its southwestern border with Kansas, and the Little Platte River crosses the county before it is dammed into Smithville Lake on the Clay County line. Missouri also divides the county into 14 historic civil townships — Carroll, Fair, Fox, Green, Kickapoo, Lee, Marshall, May, Pawnee, Pettis, Preston, Sioux, Waldron and Weston — a boundary system still used in Census and gazetteer records though it carries no local government function today.

Buchanan County lies to the north, Clinton County to the northeast, Clay County to the east, Wyandotte County, Kansas to the south, Leavenworth County, Kansas to the southwest, and Atchison County, Kansas to the northwest. Buchanan County, Clinton County, Clay County, Wyandotte County, Leavenworth County and Atchison County all border Platte directly.

Demographics

Platte County had a population of 106,718 at the 2020 census, and the latest estimate puts the county near 114,400 residents. Parkville and Platte City are the two largest communities entirely within the county, though Smithville, mostly across the line in Clay County, outnumbers both. Median household income runs near $96,227, well above Missouri’s 2023 ACS statewide figure of $68,545. Population density works out to roughly 254 people per square mile of land, dense for northwest Missouri, reflecting the county’s position inside the Kansas City metropolitan area.

Economy & Local Life

Health care and social assistance employs the most workers in the county, about 8,598 people, followed by professional, scientific and technical services at 6,404 and retail trade at 5,921. Kansas City International Airport, the county’s largest single employer site, anchors a cluster of logistics and aviation jobs on the Northland side of the county. Riverside is home to Argosy Casino Hotel & Spa, a riverboat gaming resort on the Missouri River, and the Zona Rosa retail and entertainment district sits in the Kansas City section of the county near Tiffany Springs. Parkville is home to Park University, in continuous operation there since 1875, and Weston hosts McCormick Distilling Company, the oldest continuously operated distillery in the United States, founded in 1856. The Platte County Fair, first held in 1863, is the oldest continuously operating fair west of the Mississippi River and draws crowds to the fairgrounds each summer.

History

The Platte Purchase added this land to Missouri’s northwest corner in 1837, and the Missouri legislature organized Platte County on 31 December 1838. The county takes its name from the Platte River, whose French name means a low, shallow or intermittent stream. Zadock “Zed” Martin founded Platte City, and it was incorporated as the county seat in September 1843.

Union forces burned Platte City’s original courthouse and much of the town on 16 December 1861, an episode remembered locally as the Burning of Platte City. Weston, on the Missouri River, was once the state’s second-largest river port, with more than 265 steamboat landings in 1850, before an 1881 flood shifted the river channel away from the city and ended its trade. In 1933, Bonnie and Clyde were ambushed by local authorities in a shootout just south of Platte City at the Red Crown Tourist Court.

Getting There

Interstates 29, 435 and 635 all cross Platte County, along with US Routes 69 and 71 and Missouri Routes 9, 45, 92, 152, 273 and 371.

• Kansas City — immediately south, across the Missouri River
• St. Joseph — north via Interstate 29
• Leavenworth, Kansas — southwest, across the Missouri River
• Excelsior Springs — east, across the Clay County line

Kansas City International Airport, inside the county itself, is the region’s main commercial airport. Amtrak’s Missouri River Runner and Southwest Chief trains stop at Kansas City Union Station, across the river in downtown Kansas City.

Frequently Asked Questions

Where is Platte County located?
It sits in Missouri’s northwest corner on the Kansas City metropolitan area’s Northland side, bordered by Buchanan, Clinton, Clay, Wyandotte, Leavenworth and Atchison counties.

What is the population of Platte County?
106,718 at the 2020 census, with a 2025 estimate near 114,400.

How big is Platte County?
420 square miles (1,100 km2) of land, plus about 6.6 square miles of water along the Missouri River.

What is the county seat of Platte County?
Platte City, incorporated in 1843, is the county seat.

How many towns and cities are in Platte County?
Fifteen incorporated cities, four incorporated villages, one census-designated place (New Market) and eleven unincorporated communities.

What ZIP codes does Platte County use?
64079 for Platte City and Tracy; 64089 for Smithville; 64018, 64439, 64444 and 64028 for Camden Point, Dearborn, Edgerton and Farley; 64163 for Ferrelview; 64098 for Weston; 64150 for Riverside; 64151 for the Northland communities of Houston Lake, Lake Waukomis, Northmoor and Platte Woods; and 64152–64153 for Parkville and Weatherby Lake.

What is Platte County known for?
Kansas City International Airport, the Argosy Casino in Riverside, Park University in Parkville, and McCormick Distilling Company in Weston, the oldest continuously operated distillery in the United States.

More counties in this state: Towns and villages in Missouri.