Platte County area

Population and density of Platte County

The Census Bureau estimates that 114,400 people lived in Platte County on July 1, 2025. That ranks #568 of 3,222 county equivalents nationally and #11 of 115 in Missouri. Since the April 1, 2020 estimates base of 106,724, the population has grown by 7,676 (+7.2%), compared with +1.9% for Missouri as a whole.

With 419.8 square miles of land, that is 272 people per square mile (105 per km²), placing Platte County #544 nationally for density and #9 in Missouri. The median county equivalent has 47 people per square mile; the Missouri median is 31. Put another way, there are about 2.3 acres of land per resident.

U.S. Census Bureau, Vintage 2025 population estimates. Estimates are revised each year and are not decennial census counts. Density divides the whole population by the whole county’s land area, so it describes an average, not how settlement is distributed within the county. Population sources and methods.

Cities and towns in Platte County

19 incorporated places lie at least partly in Platte County. Together they are home to 83,507 people (73%); the other 30,893 (27%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Kansas City city, with 56,064 residents in the county (the city extends into 3 other counties). The county seat, Platte City city, has 4,911 residents. Among places with at least 1,000 residents in 2020, Parkville city grew fastest since then (+26.6%).

Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Platte County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.

Metropolitan area

Platte County is a central county of the Kansas City, MO-KS Metropolitan Statistical Area. Its 14 county equivalents have 2,270,682 residents on 7,256.8 square miles of land; Platte County accounts for 5.8% of the land and 5% of the residents. By combined land it ranks #25 of 393 metropolitan areas, and #31 by population. It belongs to the Kansas City-Overland Park-Kansas City, MO-KS Combined Statistical Area.

ZIP codes

20 ZIP Code Tabulation Areas have land in Platte County; 14 of them have most of their land inside the county, and the others mainly cover neighboring areas.

6401864028640796408964092640986411864150641516415264153641546415564163641646443964440644446448464492

ZIP Code Tabulation Areas are the Census Bureau’s approximations of USPS ZIP Code service areas, from the 2020 Census relationship files. Lighter codes have less than half of their land in this county. Post-office-box and single-address ZIP Codes have no tabulation area.

Counties bordering Platte County

Platte County shares a land border with 6 county equivalents, including 3 in Kansas. It has more land than 4 of them. The largest neighbor is Leavenworth County (463.4 mi²) and the smallest is Wyandotte County (151.6 mi²). Together with its neighbors, Platte County forms a block of 2,690.9 mi² of land, of which it holds 15.6%.

How big is Platte County compared with U.S. states?

Platte County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 2.5 times as much. Missouri’s county land could hold about 164 areas the size of Platte County.

Another way to picture it: the same land area would fill a square about 20.5 miles (33 km) on each side. Real county shapes are rarely square, so this is a scale reference rather than a width or driving distance.

State figures are the sums of each state’s county-equivalent land measurements in the same Census release, so states and counties are compared on the same basis. Published state totals can differ slightly because of rounding. Compare all states · Counties bigger than entire states.

What stands out about Platte County?

Platte County has more land than 808 of the other 3,221 county equivalents in the dataset.

A median is the middle county-equivalent measurement, not the average of the largest and smallest. All three bars use the same linear scale. Very small areas may appear as a thin sliver; the labels retain their values.

Does including water change its rank?

Using land plus water places Platte County at #2,459 nationally by total area, 45 places farther from the top than its land rank. Other county equivalents gain more area when their water measurements are included.

Its water share is 1.5%, compared with a national county-equivalent median of 1.2% — 0.4 percentage points higher. This describes the statistical geography’s land/water mix, not flood exposure or developable land.

Closest positions in the national land ranking

These entries sit immediately beside Platte County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Calculated from the same Census release as the area table. Total-area order uses original ALAND + AWATER; water shares and chart labels use published square miles. Calculation details.