Linn County area

Linn County, Kansas covers 606.4 square miles: 594.1 square miles of land and 12.3 square miles of water. Its county seat is Mound City. An estimated 9,950 people lived there in 2025.

Official Census measurements · GEOID 201072026 Gazetteer · retrieved September 27, 2026
Land area594.1 mi²
Water area12.3 mi²
Population (2025)9,950
People per mi²17

County outline

Generalized outline of Linn County, Kansas
2025 Census cartographic boundary, fitted to this frame. County maps are not at a common scale. The 2026 area measurements below come from the separate Gazetteer release. Map source and limitations.

Where Linn County is located

Linn County highlighted on a map of all U.S. county equivalents. About the maps

Area breakdown

Land accounts for 98% of Linn County’s measured area and water for 2%. Its combined area converts to 1,570.6 square kilometers or approximately 388,093 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land594.0811,538.663380,211.8
Water12.31431.8937,881
Total606.3951,570.556388,092.8

How Linn County compares

By original Census land area, Linn County ranks #83 of 105 in Kansas and #1646 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 0.814 times the Kansas county-equivalent median of 729.7 square miles. It accounts for 0.7% of the combined county land area in the state.

See the complete Kansas ranking · What counts as a county equivalent?

Population and density of Linn County

The Census Bureau estimates that 9,950 people lived in Linn County on July 1, 2025. That ranks #2,486 of 3,222 county equivalents nationally and #39 of 105 in Kansas. Since the April 1, 2020 estimates base of 9,600, the population has grown by 350 (+3.6%), compared with +1.3% for Kansas as a whole.

With 594.1 square miles of land, that is 17 people per square mile (6.5 per km²), placing Linn County #2,421 nationally for density and #38 in Kansas. The median county equivalent has 47 people per square mile; the Kansas median is 8.1. Put another way, there are about 38 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate9,5959,7559,7809,9009,8649,950
Change—+160+25+120−36+86

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 Linn County

7 incorporated places lie at least partly in Linn County. Together they are home to 4,668 people (46.9%); the other 5,282 (53.1%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Pleasanton city, with 1,186 residents in the county. The county seat, Mound City city, has 639 residents. By land, Linn Valley city is the largest at 3.18 mi².

Incorporated placePopulation 2025Since 2020Land mi²
Pleasanton city1,186−2.3%2.168
Linn Valley city1,162+21.7%3.18
La Cygne city1,013−3.1%1.546
Mound City cityCounty seat639−2%1.156
Parker city232−3.7%0.281
Blue Mound city220−1.3%0.636
Prescott city216+3.8%0.285

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

Metropolitan area

Linn 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; Linn County accounts for 8.2% of the land and 0.4% 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.

County equivalentPopulation 2025Land mi²
Jackson CountyMissouri732,994604.7
Johnson County636,906473.6
Clay CountyMissouri265,032397.7
Wyandotte County170,597151.6
Cass CountyMissouri115,859696.6
Platte CountyMissouri114,400419.8
Leavenworth County84,590463.4
Miami County36,240575.9
Lafayette CountyMissouri33,531628.3
Ray CountyMissouri23,398569
Clinton CountyMissouri21,661418.9
Bates CountyMissouri16,512836.7
Linn County9,950594.1
Caldwell CountyMissouri9,012426.4

ZIP codes

11 ZIP Code Tabulation Areas have land in Linn County; 7 of them have most of their land inside the county, and the others mainly cover neighboring areas.

6601066014660266603366040660566607266075667386675466767

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 Linn County

Linn County shares a land border with 5 county equivalents, including 2 in Missouri. It has more land than 2 of them. The largest neighbor is Bates County (836.7 mi²) and the smallest is Miami County (575.9 mi²). Together with its neighbors, Linn County forms a block of 4,048.2 mi² of land, of which it holds 14.7%.

Map of Linn County and the 5 county equivalents that border it Anderson County, Kansas: 579.6 mi² landBourbon County, Kansas: 635.5 mi² landMiami County, Kansas: 575.9 mi² landBates County, Missouri: 836.7 mi² landVernon County, Missouri: 826.4 mi² land
Linn County (dark) and its bordering county equivalents. Select a neighbor to open its profile. Drawn from the 2025 Census cartographic boundaries in an equal-area projection. How borders are determined.
Bordering county equivalentLand mi²Size vs. LinnCompare
Bates CountyMissouri836.71.4× largerCompare
Vernon CountyMissouri826.41.4× largerCompare
Bourbon County635.51.1× largerCompare
Anderson County579.6about the sameCompare
Miami County575.9about the sameCompare

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

Linn County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.7 times as much. Kansas’s county land could hold about 138 areas the size of Linn County.

Land area: Linn County and the closest-sized states
Linn County594.1 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 24.4 miles (39.2 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 Linn County?

Linn County has more land than 1,576 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Linn County594.1 mi²
Kansas median729.7 mi²
National median604.5 mi²

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 Linn County at #1,722 nationally by total area, 76 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 2%, compared with a national county-equivalent median of 1.2% — 0.9 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 Linn County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#1645Autauga County, Alabama594.5Compare
#1646Linn County, Kansas594.1This county
#1647Leflore County, Mississippi594.1Compare

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.

Representative coordinates

The Census internal point is 38.216549, -94.844932. It represents a location inside the geography; it is not necessarily the centroid or the address of a courthouse.

Source and precision

U.S. Census Bureau, 2026 Gazetteer Files, Counties. Original ALAND: 1,538,662,700 m²; AWATER: 31,893,230 m². Rankings use ALAND; exact ties use ascending GEOID. Tables preserve Census-published square miles to three decimals, with conversions based on those values.

Download the official county source ZIP ↗ · Methodology

Common questions

How big is Linn County?

Linn County, Kansas has 594.1 square miles (1,538.7 km²) of land and 12.3 square miles of water, for a total area of 606.4 square miles. It ranks #1646 of 3,222 U.S. county equivalents by land area.

Is Linn County the largest county in Kansas?

No. Linn County ranks #83 of 105 in Kansas by land area. The largest is Butler County, with 1,429.7 square miles of land.

What counties border Linn County?

Linn County shares a land border with Anderson County, Bourbon County, Miami County, Bates County, Missouri, and Vernon County, Missouri.

What is the population of Linn County?

The Census Bureau estimates Linn County had 9,950 residents on July 1, 2025, ranking #2,486 of 3,222 county equivalents. That is 17 people per square mile of land.

What is the county seat of Linn County?

The county seat of Linn County is Mound City.

What cities and towns are in Linn County?

Linn County has 7 incorporated places. The most populous five are Pleasanton city, Linn Valley city, La Cygne city, Mound City city, and Parker city; 5,282 residents live outside any incorporated place.

Is Linn County part of a metropolitan area?

Yes. It is an outlying county of the Kansas City, MO-KS Metropolitan Statistical Area, which has 14 county equivalents and 2,270,682 residents.

How many ZIP codes are in Linn County?

11 ZIP Code Tabulation Areas have land in Linn County, and 7 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.

How does Linn County compare with U.S. states?

It has less land than every state. Rhode Island, the smallest, has 1.7 times as much land.

How many acres of land are in Linn County?

The land measurement converts to approximately 380,212 acres. Including water, total area is approximately 388,093 acres. One square mile equals 640 acres.

Why might another source show a different area?

Check whether it reports land or total area, its Census vintage, and its rounding. Our guide explains how to reconcile county area figures.

Can this establish a property boundary?

No. Statistical measurements and generalized maps do not establish property lines. Consult the relevant local surveying or land-records authority.

Cite this county

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