7th most populous of 115
With 231,888 residents in 2024, Jefferson County ranks 7th by population among Missouri's 115 counties and is home to 3.7% of the state's residents.

Jefferson County has the 8th highest median household income in Missouri ($82,851) and the 11th largest economy ($6.9 billion GDP).
Jefferson County is home to 231,888 people (2024 estimate) on 656 square miles of land. This page brings together official U.S. Census Bureau population estimates since 2000, the components of change—births, deaths and migration—American Community Survey indicators on income, housing, poverty and education, BEA economic accounts and BLS unemployment.
Pick an indicator to see its long-run evolution.
U.S. Census Bureau: intercensal estimates 2000–2009, Vintage 2020 (2010–2019) and Vintage 2024 (2020–2024), July 1.
| Indicator | Value | Year and source |
|---|---|---|
| Population estimate | 231,888 | 2024 · U.S. Census Bureau |
| Population, 2010 Census | 218,733 | 2010 · U.S. Census Bureau |
| Population, 2000 | 198,937 | July 1, 2000 · Census intercensal |
| Change since 2000 | +16.6% | 2000–2024 · Census |
| International migration | +121 | 2024 · Census Vintage 2024 |
| Domestic migration | +832 | 2024 · Census Vintage 2024 |
| Birth rate | 9.1 per 1,000 | 2024 · calculated |
| Death rate | 10.0 per 1,000 | 2024 · calculated |
| Population rank in Missouri | 7th of 115 | 2024 · calculated |
| Per capita personal income | $56,907 | BEA, 2024 · official |
| Gross domestic product | $6.9 billion | BEA, current dollars, 2024 · official |
| Median household income | $82,851 | ACS 2020–2024 5-year · official |
| Poverty rate | 9.0% | ACS 2020–2024 5-year · official |
| Bachelor’s degree or higher | 24.7% | Age 25+, ACS 2020–2024 5-year · official |
| Foreign-born residents | 2.3% | ACS 2020–2024 5-year · official |
| Median home value | $237,200 | ACS 2020–2024 5-year · official |
| Median gross rent | $979/month | ACS 2020–2024 5-year · official |
| Median age | 40.3 years | ACS 2020–2024 5-year · official |
| Households | 88,309 | ACS 2020–2024 5-year · official |
| Owner-occupied homes | 82.2% | ACS 2020–2024 5-year · official |
Comparable indicators for Jefferson County, Missouri and the United States.
| Indicator | County | Missouri | U.S. | Reference |
|---|---|---|---|---|
| Population change 2020–2024 | +2.3% | +1.5% | +2.6% | Census Vintage 2024 |
| Birth rate (per 1,000) | 9.1 | 10.8 | 10.6 | 2024 |
| Death rate (per 1,000) | 10.0 | 10.6 | 9.1 | 2024 |
| Net migration rate (per 1,000) | 4.1 | 5.7 | 8.2 | 2024 |
| Population density (/mi²) | 353.3 | 90.8 | 96.3 | 2024 |
| Per capita personal income | $56,907 | $64,920 | $73,204 | BEA, 2024 |
| Median household income | $82,851 | $70,702 | $80,734 | ACS 2020–2024 5-year |
| Poverty rate | 9.0% | 12.6% | 12.5% | ACS 2020–2024 5-year |
| Bachelor’s degree or higher | 24.7% | 32.4% | 35.7% | Age 25+, ACS 2020–2024 5-year |
| Foreign-born residents | 2.3% | 4.5% | 14.1% | ACS 2020–2024 5-year |
| Median home value | $237,200 | $230,300 | $332,700 | ACS 2020–2024 5-year |
| Median gross rent | $979/month | $1,033/month | $1,413/month | ACS 2020–2024 5-year |
| Median age | 40.3 years | 39.0 years | 38.9 years | ACS 2020–2024 5-year |
| Owner-occupied homes | 82.2% | 68.1% | 65.2% | ACS 2020–2024 5-year |
With 231,888 residents in 2024, Jefferson County ranks 7th by population among Missouri's 115 counties and is home to 3.7% of the state's residents.
Its population went from 198,937 in 2000 to 231,888 in 2024, a change of +16.6%, compared with +11.4% for Missouri as a whole.
In the year to July 2024 the county recorded 2,103 births and 2,330 deaths, so deaths outnumbered births by 227.
Annual Census estimates since 2000 put the county's highest population in 2024, at 231,888.
Jefferson County has about 353.3 residents per square mile of land, ranking 7th of 115 counties; Missouri averages 90.8.
With a median household income of $82,851 (ACS 2020–2024 5-year), the county ranks 8th of 115 Missouri counties; the state median is $70,702.
Its economy produced $6.9 billion of GDP in 2024 (BEA), 11th largest among 115 Missouri counties.
Real GDP grew 2.7% in 2024, adjusted for inflation (BEA, chained 2017 dollars).