Lake St. Louis

County:: St. Charles County
County Seat:: No
Area (mi²):: 8.54
State:: Missouri

Lake St. Louis is a city located in St. Charles County, Missouri. Lake St. Louis has a 2025 population of 19,910. Lake St. Louis is currently growing at a rate of 3.24% annually and its population has increased by 18.6% since the most recent census, which recorded a population of 16,787 in 2020.

The average household income in Lake St. Louis is $148,931 with a poverty rate of 4.05%. The median age in Lake St. Louis is 43.2 years: 41.7 years for males, and 44.7 years for females.

Demographics

The racial composition of Lake St. Louis includes 87.57% White, 4.24% Black or African American, and smaller percentages for Asian, other race, Native American, Native Hawaiian or Pacific Islander and multiracial populations.

Population by Race

White

Two or more races

Black or African American

Asian

Other race

Native American

Native Hawaiian or Pacific Islander

Race	Population	Percentage (of total)
White	15,358	87.57%
Two or more races	975	5.56%
Black or African American	744	4.24%
Asian	273	1.56%
Other race	178	1.01%
Native American	10	0.06%
Native Hawaiian or Pacific Islander	0	0%

Lake St. Louis Marital Status

Married

Widowed

Divorced

Separated

Never Married

Economics and Income Statistics

Lake St. Louis' average per capita income is $73,744. Household income levels show a median of $123,427. The poverty rate stands at 4.05%.

Families: A family includes the owner or renter of the home along with everyone related to them - whether through birth, marriage, or adoption. This includes relatives like spouses, children, parents, siblings, grandparents, and any other family members.

Households: A household includes all the people who occupy a housing unit (such as a house or apartment) as their usual place of residence.

Non Families: A nonfamily household is either someone living alone or when the owner/renter lives with people they aren't related to, like roommates.

Name	Median	Mean
Married Families	$157,753	-
Families	$151,721	$174,546
Households	$123,427	$148,931
Non Families	$53,474	$74,883

$73,744

Average Income

$123,427

Median Household Income

4.05%

Poverty Rate