• county
  • FIPS 29099
  • Largest town: Arnold

Jefferson County, Missouri

Jefferson County had 231,888 residents in the Census Vintage 2024 estimate, on 656.3 square miles of land. It ranks 7th of 115 in Missouri by population and 39th by land area.

Population
231,888
#7 of 115 in Missouri · #311 in US
Area
656.3 sq mi
#39 of 115 in Missouri · #1,433 in US
Density
353 / sq mi
#7 of 115 in Missouri · #381 in US
Median household income
$81,517
#6 of 115 in Missouri · #425 in US

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

Jefferson County within Missouri. Pin: Jefferson City.

Measure from here

Tools and pages that start from Jefferson County

Jefferson County population, land area and income

Jefferson County had 231,888 residents in the Census Vintage 2024 estimate, on 656.3 square miles of land. It ranks 7th of 115 in Missouri by population and 39th by land area. That works out to 353.3 people per square mile, 3.7 times the US average of 96.3, and in the top quarter nationally.

The median county-equivalent in Missouri has 19,100 residents, so Jefferson County is 12.1 times that size.

Its SAIPE 2023 median household income of $81,517 is in the top quarter among 3,143 counties with an estimate.

National rank among 3,144

Population

231,888

3144th1st

311th of 3,144 (US)

Land area

656 sq mi

3144th1st

1433rd of 3,144 (US)

Density

353.3 / sq mi

3144th1st

381st of 3,144 (US)

Median household income

$81,517

3143rd1st

425th of 3,143 (US)

Rank within Missouri (115)

Population

231,888

115th1st

7th of 115 (MO)

Land area

656 sq mi

115th1st

39th of 115 (MO)

Density

353.3 / sq mi

115th1st

7th of 115 (MO)

Median household income

$81,517

115th1st

6th of 115 (MO)

How Jefferson County's population changed since 2020

Jefferson County gained 4,941 residents between the July 2020 and July 2024 estimates, a rise of 2.2%. That ranks 45th of 115 in Missouri for growth. The median Missouri county changed by +1.4%, and the state as a whole by +1.5%.

Since the April 2020 estimates base, Jefferson County recorded 9,690 births and 10,464 deaths, a natural change of -774. Net international migration added +301 and net domestic migration, people moving to or from other US counties, came to +5,670. The largest single component was domestic migration, which added 5,670 people.

226.9k2020228.0k2021229.3k2022231.2k2023231.9k2024
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
9,690
Deaths
10,464
Net international migration
+301
Net domestic migration
+5,670
Change, July 2023 to July 2024
+733

Where Jefferson County is

The Census internal point of Jefferson County is at 38.257600, -90.543700. It sits in UTM zone 15N. The map shades Missouri's 115 county-equivalents by population change from 2020 to 2024, darker for faster growth, with Jefferson County outlined. Dots are towns of 1,000+ people with residents in it.

Pettis County: +1.8%Henry County: +2.7%Texas County: +5.7%Madison County: +1.8%St. Louis city: -6.9%Cole County: +1.3%Washington County: +0.6%Macon County: -0.1%Barton County: +0.8%Grundy County: +0.1%Cedar County: +5.7%Randolph County: -1.6%Ray County: +0.3%Caldwell County: +2.0%Benton County: +6.1%Douglas County: +5.9%Shannon County: +3.4%Dade County: +0.5%Wright County: +7.1%Gentry County: +2.6%Lawrence County: +3.0%Cooper County: +2.9%Hickory County: +5.6%Moniteau County: +0.5%Dent County: +2.3%Monroe County: +2.3%Maries County: +0.7%Bollinger County: +0.5%Clinton County: +2.4%Knox County: +0.0%Webster County: +7.8%Harrison County: +0.4%Pulaski County: -0.1%Adair County: +1.5%Warren County: +7.7%Daviess County: +1.3%Audrain County: -1.9%Howard County: -0.1%Linn County: +0.4%Saline County: -0.1%Miller County: +3.6%Dallas County: +4.3%Morgan County: +6.7%New Madrid County: -6.8%Newton County: +4.8%Oregon County: +1.0%Franklin County: +2.3%Greene County: +2.9%Ralls County: +1.4%Lafayette County: +1.4%Livingston County: +4.8%McDonald County: +3.3%Barry County: +3.1%Cape Girardeau County: +2.2%Carroll County: -0.6%Christian County: +7.6%Vernon County: +0.6%Carter County: +3.0%Andrew County: -0.1%Jasper County: +2.9%Worth County: -4.9%Lincoln County: +10.1%Marion County: -0.2%Holt County: +1.2%Howell County: +2.4%St. Francois County: +1.6%Chariton County: +0.1%Butler County: -0.6%Iron County: -1.0%Perry County: +0.7%Cass County: +5.3%St. Louis County: -1.0%Dunklin County: -4.3%Wayne County: -1.1%Ozark County: +6.7%Laclede County: +1.9%Reynolds County: -2.5%Lewis County: -1.9%Taney County: +1.2%Ripley County: +0.4%Ste. Genevieve County: +0.4%Scotland County: -0.1%Putnam County: -3.1%Schuyler County: +1.5%Shelby County: -2.8%Boone County: +4.4%Mercer County: -1.7%Platte County: +5.6%Camden County: +3.1%Bates County: +2.1%Johnson County: +3.4%Sullivan County: -3.8%Atchison County: -3.1%Scott County: -0.2%Montgomery County: +2.0%Jefferson County: +2.2%Clark County: -0.5%Callaway County: +1.8%St. Clair County: +5.4%Buchanan County: -1.1%Pemiscot County: -7.6%Polk County: +4.6%Phelps County: +2.5%Stone County: +4.6%Osage County: +1.7%Clay County: +3.6%Nodaway County: -2.4%Crawford County: -1.0%Jackson County: +1.4%St. Charles County: +4.3%Mississippi County: -3.1%Pike County: +3.1%Stoddard County: -0.7%Gasconade County: -0.7%DeKalb County: -14.8%
Change 2020 to 2024
  1. < -0.7%
  2. < +0.5%
  3. < +2.0%
  4. < +3.6%
  5. ≥ +3.6%
no data

Orange pin: Jefferson County internal point. Dark pin: Jefferson City.

Internal point

Decimal
38.257600, -90.543700
DMS
38°15'27.36"N 90°32'37.32"W
UTM
15N 714915.5E 4237250.4N
Geohash
9yz9ess4d
Plus code
86CF7F54+2G

Towns in Jefferson County

9 incorporated places of 1,000+ people have residents in Jefferson County, 64,153 people together, or 28% of the county. Each figure counts only the part of the town inside Jefferson County; towns marked "part" extend into another county. The largest is Arnold with 21,036.

  1. 01Arnold21,036
  2. 02Festus13,730
  3. 03De Soto6,503
  4. 04Pevely6,103
  5. 05Herculaneum5,321
  6. 06Crystal City4,703
  7. 07Hillsboro3,489
  8. 08Byrnes Mill3,189
  9. 09Eureka (part)79
Census Vintage 2024 subcounty estimates, county parts of incorporated places (SUMLEV 157).

Counties bordering Jefferson County

The Census 2024 county adjacency file lists 6 neighbors for Jefferson County, including 1 across a state line. The most populous is St. Louis County, MO, with 992,929 residents. Distances run between Census internal points in a straight line.

Distance to Jefferson City and the nearest big city

Jefferson City is 91.0 miles WNW of Jefferson County's internal point in a straight line. The nearest place of 100,000 or more is St. Louis, MO (population 279,695), 30.8 miles away. The nearest place of 10,000 or more is Festus, MO (population 13,730), 7.8 miles away.

Jefferson County FIPS code

The FIPS code of Jefferson County is 29099: state code 29 for Missouri plus county code 099. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $81,517.

Questions people ask

What is the population of Jefferson County, Missouri?

The Census Vintage 2024 estimate for July 1, 2024 is 231,888. That is up 4,941 people (2.2%) from the July 2020 estimate of 226,947.

What is the FIPS code of Jefferson County?

29099. The first two digits (29) are Missouri; the last three (099) identify the county.

What is the largest town in Jefferson County?

Arnold, with 21,036 residents inside Jefferson County in 2024.

Which counties border Jefferson County?

6 county-equivalents border it in the Census 2024 adjacency file: St. Louis County, MO; Franklin County, MO; St. Francois County, MO; Monroe County, IL; Washington County, MO; Ste. Genevieve County, MO.

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.