City in St. Charles County, Missouri · 8.5 sq mi · 2,308 people per sq mi
About 20,000 people live in Lake St. Louis. The typical household earns $125,693, and the median resident is 42.7 years old.
2026 projection
From 16,804 in 2020
Poverty rate 4.35%
Men 40.9 · Women 44.2
1980–2026
19,707
2026 projection
17.3% since 2020 (increase)
Source: U.S. Census Bureau decennial counts and annual estimates. 2026 is a projection. Values between recorded years are interpolated.
Use the left and right arrow keys to inspect population observations.
1980–2026
19,707
2026 projection
17.3% since 2020 (increase)
Source: U.S. Census Bureau decennial counts and annual estimates. 2026 is a projection. Values between recorded years are interpolated.
Use the left and right arrow keys to inspect population observations.
| 2026 | 19,707 | +578 | 3.02% |
|---|---|---|---|
| 2025 | 19,129 | +12 | 0.06% |
| 2024 | 19,117 | +420 | 2.25% |
| 2023 | 18,697 | +353 | 1.92% |
| 2022 | 18,344 | +1,009 | 5.82% |
| 2021 | 17,335 | +531 | 3.16% |
| 2020 | 16,804 | -42 | 0.25% |
| 2019 | 16,846 | +642 | 3.96% |
| 2018 | 16,204 | +285 | 1.79% |
| 2017 | 15,919 | +198 | 1.26% |
Showing 10 of 20 years.
U.S. Census Bureau, 2024 ACS 5-year estimates · Table S0101
Each square is about 1% of residents (roughly 181 people).
Hispanic or Latino residents can be of any race. All other groups exclude Hispanic residents.
U.S. Census Bureau, 2024 ACS 5-year estimates · Table B03002
Half of households earn more, half earn less
Typical yearly pay for a worker 25 or older.
About 1 in 23 residents
62% of residents age 15 and older are married.
| Status | Overall | Male | Female |
|---|---|---|---|
| Married | 62% | 62% | 61% |
| Never married | 26% | 30% | 22% |
| Divorced | 7% | 5% | 10% |
| Widowed | 4% | 2% | 6% |
| Separated | <1% | <1% | 1% |
U.S. Census Bureau, 2024 ACS 5-year estimates · Table S1201
10 sources, all from the U.S. Census Bureau