Lake St. Louis, Missouri

Lake St. Louis population, 2020 to 2024

Lake St. Louis added 2,371 residents from July 2020 to July 2024, a change of +14.1%. In the latest year it moved by +449. Among 135 Missouri places of 5,000 or more, that growth ranks 6th; the median place changed by +1.2%. The median place of 5,000+ in Missouri has 12,239 people, so Lake St. Louis is 1.6 times that size.

Lake St. Louis covers 8.55 square miles of land and 0.81 of water, for 2,241 people per square mile of land. The median Missouri place of 5,000+ has 1,448, so Lake St. Louis is denser than the typical town.

What county Lake St. Louis is in

All of Lake St. Louis's residents live in St. Charles County, which had 423,726 residents in 2024. Lake St. Louis holds 4.5% of the county's population. The shaded shape is on the map above; dots mark the eight nearest places.

ZIP codes in Lake St. Louis

1 ZIP Code Tabulation Area (ZCTA) overlaps Lake St. Louis by at least 10% of the ZCTA's or the city's land: 63367. ZCTAs are Census approximations of USPS ZIP code delivery areas. The list comes from the 2020 ZCTA to place relationship file, so a city that annexed land after 2020 may reach into ZIP codes not listed here.

Where Lake St. Louis is

The Census internal point of Lake St. Louis is at 38.779900, -90.785600. Jefferson City, the capital, is 76.1 miles W in a straight line. The nearest larger place is O'Fallon, MO (95,355 people), 3.5 miles away. The nearest city of 100,000 or more is St. Louis, MO, 30.8 miles away.

Daylight in Lake St. Louis

At 38.78° N, Lake St. Louis gets about 14 h 53 min of daylight around the June solstice and 9 h 27 min around the December solstice, a swing of 5 h 26 min. Figures are sunrise to sunset from the SunCalc model for June 21 and December 21, 2026.

Places near Lake St. Louis

The eight nearest incorporated places of 1,000+ in Missouri, measured between internal points. The closest is O'Fallon, 3.5 miles away, with 95,355 people.