Leavenworth County area

Population and density of Leavenworth County

The Census Bureau estimates that 84,590 people lived in Leavenworth County on July 1, 2025. That ranks #702 of 3,222 county equivalents nationally and #6 of 105 in Kansas. Since the April 1, 2020 estimates base of 81,909, the population has grown by 2,681 (+3.3%), compared with +1.3% for Kansas as a whole.

With 463.4 square miles of land, that is 183 people per square mile (70 per km²), placing Leavenworth County #676 nationally for density and #6 in Kansas. The median county equivalent has 47 people per square mile; the Kansas median is 8.1. Put another way, there are about 3.5 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 Leavenworth County

8 incorporated places lie at least partly in Leavenworth County. Together they are home to 63,451 people (75%); the other 21,139 (25%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Leavenworth city, with 37,012 residents in the county. By land, De Soto city is the largest at 25.9 mi² across all its counties. Among places with at least 1,000 residents in 2020, Basehor city grew fastest since then (+19.2%).

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

Metropolitan area

Leavenworth County is an outlying 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; Leavenworth County accounts for 6.4% of the land and 3.7% 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

13 ZIP Code Tabulation Areas have land in Leavenworth County; 8 of them have most of their land inside the county, and the others mainly cover neighboring areas.

66002660076601266020660276604366044660486605266054660866609766109

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 Leavenworth County

Leavenworth County shares a land border with 6 county equivalents, including 1 in Missouri. It has more land than 4 of them. The largest neighbor is Jefferson County (532.6 mi²) and the smallest is Wyandotte County (151.6 mi²). Together with its neighbors, Leavenworth County forms a block of 2,928.1 mi² of land, of which it holds 15.8%.

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

Leavenworth County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 2.2 times as much. Kansas’s county land could hold about 176 areas the size of Leavenworth County.

Another way to picture it: the same land area would fill a square about 21.5 miles (34.6 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 Leavenworth County?

Leavenworth County has more land than 1,004 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 Leavenworth County at #2,287 nationally by total area, 69 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 1.2%, compared with a national county-equivalent median of 1.2%. The two percentages are within 0.1 percentage points of each other. 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 Leavenworth 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.