• county
  • FIPS 20091
  • Largest town: Overland Park

Johnson County, Kansas

Johnson County had 632,276 residents in the Census Vintage 2024 estimate, on 473.6 square miles of land. It is the most populous of Kansas's 105 county-equivalents.

Population
632,276
#1 of 105 in Kansas · #113 in US
Area
473.6 sq mi
#99 of 105 in Kansas · #2,178 in US
Density
1,335 / sq mi
#1 of 105 in Kansas · #121 in US
Median household income
$103,085
#1 of 105 in Kansas · #107 in US

Census Vintage 2024 estimates · SAIPE 2023 income · 2024 Gazetteer land area

Johnson County within Kansas. Pin: Topeka.

Measure from here

Tools and pages that start from Johnson County

Johnson County population, land area and income

Johnson County had 632,276 residents in the Census Vintage 2024 estimate, on 473.6 square miles of land. It is the most populous of Kansas's 105 county-equivalents. That works out to 1,335.0 people per square mile, 13.9 times the US average of 96.3, and in the top tenth nationally.

The median county-equivalent in Kansas has 6,946 residents, so Johnson County is 91.0 times that size.

Its SAIPE 2023 median household income of $103,085 is in the top tenth among 3,143 counties with an estimate.

National rank among 3,144

Population

632,276

3144th1st

113th of 3,144 (US)

Land area

474 sq mi

3144th1st

2178th of 3,144 (US)

Density

1,335.0 / sq mi

3144th1st

121st of 3,144 (US)

Median household income

$103,085

3143rd1st

107th of 3,143 (US)

Rank within Kansas (105)

Population

632,276

105th1st

1st of 105 (KS)

Land area

474 sq mi

105th1st

99th of 105 (KS)

Density

1,335.0 / sq mi

105th1st

1st of 105 (KS)

Median household income

$103,085

105th1st

1st of 105 (KS)

How Johnson County's population changed since 2020

Johnson County gained 21,115 residents between the July 2020 and July 2024 estimates, a rise of 3.5%. That ranks 3rd of 105 in Kansas for growth. The median Kansas county changed by -1.0%, and the state as a whole by +1.1%.

Since the April 2020 estimates base, Johnson County recorded 29,177 births and 19,780 deaths, a natural change of +9,397. Net international migration added +11,820 and net domestic migration, people moving to or from other US counties, came to +841. The largest single component was international migration, which added 11,820 people.

611.2k2020615.0k2021619.3k2022625.4k2023632.3k2024
Census Vintage 2024 county estimates for July 1 of each year. The axis starts above zero so year-to-year changes are visible.

Components of change, April 2020 to July 2024

Births
29,177
Deaths
19,780
Net international migration
+11,820
Net domestic migration
+841
Change, July 2023 to July 2024
+6,832

Where Johnson County is

The Census internal point of Johnson County is at 38.883900, -94.822300. It sits in UTM zone 15N. The map shades Kansas's 105 county-equivalents by population change from 2020 to 2024, darker for faster growth, with Johnson County outlined. Dots are towns of 1,000+ people with residents in it.

Harper County: -1.0%Phillips County: -4.6%Seward County: -2.7%Grant County: -3.1%Pawnee County: -3.8%Haskell County: -4.5%Ness County: -2.3%Logan County: -1.8%Wichita County: -3.6%Greenwood County: -1.7%Stanton County: -0.7%Edwards County: -5.3%Gray County: +1.6%Franklin County: +1.0%Saline County: -1.5%Allen County: -0.9%Lyon County: +1.3%Cloud County: -3.3%Brown County: -3.6%Rice County: -1.1%Lincoln County: -0.6%Osborne County: -4.0%Rooks County: -2.8%Russell County: -0.8%Jefferson County: +0.0%Jewell County: -1.0%Lane County: -5.6%Sheridan County: -1.9%Gove County: -2.1%Trego County: -1.1%Montgomery County: -3.0%Sumner County: +0.1%Graham County: -1.5%Marion County: -1.0%Washington County: +0.8%Stevens County: -4.0%Kiowa County: -0.7%Mitchell County: +0.4%Cheyenne County: +1.3%Ellis County: +0.2%Rush County: -4.6%Scott County: -4.3%Comanche County: +0.7%Wallace County: -2.6%Nemaha County: -2.0%Linn County: +2.6%Ford County: -0.4%Dickinson County: +1.4%Ellsworth County: -0.9%Labette County: -2.3%Cowley County: -1.0%Neosho County: -2.2%Wilson County: -2.2%Thomas County: -1.7%Greeley County: -9.6%Osage County: -0.0%Finney County: +0.1%Kearny County: -3.8%Kingman County: -6.4%Republic County: -1.3%Ottawa County: +2.1%Smith County: -0.5%Crawford County: -0.1%Elk County: -1.5%Miami County: +4.4%Hodgeman County: -3.7%Morris County: -1.7%Morton County: -8.1%Harvey County: -1.0%Meade County: -4.2%Sedgwick County: +2.1%Geary County: -3.6%Woodson County: +0.4%Bourbon County: +0.6%Chase County: -2.6%Pratt County: -0.0%Reno County: -0.8%Chautauqua County: -1.2%Norton County: -2.1%Marshall County: -0.7%Doniphan County: +1.4%Cherokee County: -0.9%Barton County: -2.3%Riley County: +0.8%Butler County: +2.6%Stafford County: -3.7%Anderson County: +0.9%Sherman County: -1.8%Rawlins County: -5.5%Pottawatomie County: +5.7%McPherson County: +0.5%Coffey County: -0.7%Hamilton County: +0.0%Atchison County: -0.5%Shawnee County: -0.4%Leavenworth County: +3.3%Jackson County: +2.2%Clark County: -5.3%Douglas County: +2.7%Clay County: -1.9%Barber County: -3.2%Johnson County: +3.5%Wabaunsee County: +3.2%Decatur County: -1.1%Wyandotte County: +0.3%
Change 2020 to 2024
  1. < -3.6%
  2. < -1.7%
  3. < -0.7%
  4. < +0.6%
  5. ≥ +0.6%
no data

Orange pin: Johnson County internal point. Dark pin: Topeka.

Internal point

Decimal
38.883900, -94.822300
DMS
38°53'2.04"N 94°49'20.28"W
UTM
15N 341940.6E 4305471.1N
Geohash
9yut4q8e0
Plus code
86C7V5MH+H3

Towns in Johnson County

17 incorporated places of 1,000+ people have residents in Johnson County, 616,984 people together, or 98% of the county. Each figure counts only the part of the town inside Johnson County; towns marked "part" extend into another county. The largest is Overland Park with 202,893.

  1. 01Overland Park202,893
  2. 02Olathe149,035
  3. 03Shawnee69,724
  4. 04Lenexa59,427
  5. 05Leawood34,013
  6. 06Gardner25,836
  7. 07Prairie Village22,919
  8. 08Merriam11,560
  9. 09Mission10,013
  10. 10Roeland Park6,689
  11. 11De Soto6,579
  12. 12Spring Hill (part)6,227
  13. 13Fairway4,160
  14. 14Mission Hills3,521
  15. 15Westwood1,719
Census Vintage 2024 subcounty estimates, county parts of incorporated places (SUMLEV 157).

Counties bordering Johnson County

The Census 2024 county adjacency file lists 7 neighbors for Johnson County, including 2 across a state line. The most populous is Jackson County, MO, with 727,362 residents. Distances run between Census internal points in a straight line.

Distance to Topeka and the nearest big city

Topeka is 47.3 miles WNW of Johnson County's internal point in a straight line. The nearest place of 100,000 or more is Olathe, KS (population 149,035), 0.2 miles away.

Johnson County FIPS code

The FIPS code of Johnson County is 20091: state code 20 for Kansas plus county code 091. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $103,085.

Questions people ask

What is the population of Johnson County, Kansas?

The Census Vintage 2024 estimate for July 1, 2024 is 632,276. That is up 21,115 people (3.5%) from the July 2020 estimate of 611,161.

What is the FIPS code of Johnson County?

20091. The first two digits (20) are Kansas; the last three (091) identify the county.

What is the largest town in Johnson County?

Overland Park, with 202,893 residents inside Johnson County in 2024.

Which counties border Johnson County?

7 county-equivalents border it in the Census 2024 adjacency file: Jackson County, MO; Wyandotte County, KS; Douglas County, KS; Cass County, MO; Leavenworth County, KS; Miami County, KS; Franklin County, KS.

Sources and data as of

Data as of: Census Vintage 2024 population estimates, 2024 Gazetteer land area and internal points, SAIPE 2023 median household income.

  1. 01Census Vintage 2024 county population estimates
  2. 02Census 2024 Gazetteer, counties
  3. 03Census SAIPE 2023 state and county estimates
  4. 04Census Vintage 2024 subcounty population estimates
  5. 05Census 2024 county adjacency file
  6. 06Census 2024 cartographic boundary file, counties (1:5,000,000)

How every number is computed: methodology. Spotted a wrong figure? Report an error.