Census tract · St. Charles County
Census Tract 3123, St. Charles County, Missouri
Census Tract 3123, GEOID 29183312300, in St. Charles County, Missouri, partly within St. Peters and St. Charles. 2,702 residents in the ACS 2020-2024 5-year estimates (±332); the 2020 Census counted 2,730.
Residents, 2020-2024
2,702
±332 (90% margin)
2020 Census count: 2,730
Median household income
$138,618
±$23,635 (90% margin)
St. Charles County: $104,692
Median home value
$350,400
±$9,281 (90% margin)
St. Charles County: $320,800
Median gross rent
not published
St. Charles County: $1,370
Where is Census Tract 3123?
Census Tract 3123 is one of 85 census tracts in St. Charles County, Missouri. It covers 0.67 square miles of land, 4,081 residents per square mile in 2020. Its GEOID, 29183312300, names it uniquely (how tract numbers and GEOIDs work).
| Place | Share of the tract |
|---|---|
| St. Peters | 49% |
| St. Charles | 41% |
4 census tracts border Census Tract 3123: Tract 3109.03 ($87,347), Tract 3112.11 ($78,256), Tract 3112.12 ($110,714) and Tract 3112.96 ($95,982). The figure in brackets is each tract's median household income.
Whether a tract counts as low- or moderate-income for bank lending (the Community Reinvestment Act) is set by the FFIEC against its metro area's family income: look it up in the FFIEC census geocoder.
Source: 2024 Gazetteer and 2020 block assignment files, U.S. Census Bureau · Census reference files
How many people live in Census Tract 3123?
The 2020-2024 American Community Survey puts Census Tract 3123's population at 2,702 (±332) in 1,159 households; the 2020 Census counted 2,730 residents and 1,038 housing units.
| Measure | Tract 3123 | St. Charles County |
|---|---|---|
| Total population | 2,702 ±332 | 414,535 |
| Households | 1,159 ±155 | 161,311 |
| Average household size | 2.33 ±0.15 | 2.53 |
| Housing units | 1,216 ±138 | 167,163 |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026); 2020 Census P.L. 94-171 · Check it at data.census.gov
Who lives in Census Tract 3123?
The median resident of Census Tract 3123 is 55.7 years old; 13.2% are under 18 and 29.9% are 65 or older. The largest group is non-Hispanic white residents at 91.5%, then non-Hispanic residents of two or more races at 5.0%.
| Measure | Tract 3123 | St. Charles County |
|---|---|---|
| Median age | 55.7 ±3.4 | 39.8 |
| Under 18 years | 13.2% ±2.6 pts | 22.5% |
| 65 years and over | 29.9% ±6.7 pts | 17.0% |
| Hispanic or Latino (any race) | 1.9% ±2.0 pts | 4.2% |
| White alone, not Hispanic | 91.5% ±4.7 pts | 83.0% |
| Black or African American alone, not Hispanic | 0.0% ±1.3 pts | 5.0% |
| Asian alone, not Hispanic | 1.4% ±1.6 pts | 3.0% |
| American Indian and Alaska Native alone, not Hispanic | 0.0% ±1.3 pts | 0.0% |
| Native Hawaiian and Other Pacific Islander alone, not Hispanic | 0.1% ±0.3 pts | 0.0% |
| Two or more races, not Hispanic | 5.0% ±3.5 pts | 4.3% |
| Some other race alone, not Hispanic | 0.0% ±1.3 pts | 0.4% |
| Born outside the United States | 3.1% ±2.5 pts | 4.5% |
| Speak a language other than English at home (age 5+) | 3.5% ±3.2 pts | 5.8% |
| Civilian veterans (age 18+) | 7.2% ±3.9 pts | 6.6% |
| With a disability | 10.3% ±4.3 pts | 11.7% |
| No health insurance coverage | 2.3% ±1.5 pts | 4.2% |
| High school graduate or higher (age 25+) | 98.1% ±1.5 pts | 95.7% |
| Bachelor's degree or higher (age 25+) | 45.9% ±7.9 pts | 42.7% |
| Graduate or professional degree (age 25+) | 22.5% ±7.8 pts | 15.8% |
| Lived in the same house a year earlier | 90.8% ±7.6 pts | 89.6% |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profiles DP02, DP05) · Check it at data.census.gov
What do households in Census Tract 3123 earn?
Half of the 1,159 households in Census Tract 3123 earn less than $138,618 a year (±$23,635), against $104,692 across St. Charles County: 13th highest of the county's 84 tracts with a reliable estimate.
| Measure | Tract 3123 | St. Charles County |
|---|---|---|
| Median household income | $138,618 ±$23,635 | $104,692 |
| Mean household income | $146,719 ±$13,118 | $129,305 |
| Per capita income | $61,936 ±$6,165 | $51,051 |
| People below the poverty line | 3.4% ±2.5 pts | 5.2% |
| Children under 18 below the poverty line | 0.0% ±9.3 pts | 5.7% |
| Households receiving SNAP | 0.0% ±3.0 pts | 3.6% |
| Households with a computer | 97.5% ±2.3 pts | 97.4% |
| Households with a broadband subscription | 97.5% ±2.3 pts | 95.1% |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP03) · Check it at data.census.gov
What does housing cost in Census Tract 3123?
Owners occupy 97.4% of Census Tract 3123's occupied homes and renters 2.6%. The median owner-occupied home is valued at $350,400 by its owner (±$9,281).
| Measure | Tract 3123 | St. Charles County |
|---|---|---|
| Median home value (owner-occupied) | $350,400 ±$9,281 | $320,800 |
| Renters paying 35% or more of income on rent | 0.0% ±56.2 pts | 34.5% |
| Median monthly owner costs, with a mortgage | $2,124 ±$184 | $1,866 |
| Owner-occupied homes | 97.4% ±3.0 pts | 80.5% |
| Renter-occupied homes | 2.6% ±3.0 pts | 19.5% |
| Housing units | 1,216 ±138 | 167,163 |
| Single-family detached homes | 95.3% ±4.3 pts | 74.7% |
| Mobile homes | 0.0% ±2.8 pts | 2.5% |
| Built 2020 or later | 4.7% ±4.3 pts | 3.3% |
| Built 2010 to 2019 | 0.0% ±2.8 pts | 14.4% |
| Built 1939 or earlier | 0.0% ±2.8 pts | 2.2% |
| Households with no vehicle | 1.8% ±2.2 pts | 3.8% |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP04) · Check it at data.census.gov
How do people in Census Tract 3123 get to work?
68.7% of Census Tract 3123's workers drive alone and 25.7% work from home. The average trip to work takes 22.1 minutes.
| Measure | Tract 3123 | St. Charles County |
|---|---|---|
| In the labor force (age 16+) | 58.7% ±7.2 pts | 69.4% |
| Unemployment rate | 2.8% ±2.4 pts | 2.9% |
| Drove alone to work | 68.7% ±9.0 pts | 73.8% |
| Carpooled | 5.6% ±3.8 pts | 5.9% |
| Public transportation | 0.0% ±2.6 pts | 0.1% |
| Walked | 0.0% ±2.6 pts | 0.8% |
| Worked from home | 25.7% ±7.4 pts | 18.0% |
| Mean travel time to work | 22.1 min ±1.9 | 24.5 min |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP03) · Check it at data.census.gov
How does Census Tract 3123 compare with the other tracts in St. Charles County?
Among St. Charles County's tracts with a reliable estimate, Census Tract 3123 ranks as shown below (1 = highest).
| Measure | In St. Charles County |
|---|---|
| Population | 76th of 84 |
| Residents per square mile | 13th of 85 |
| Median household income | 13th of 84 |
| Per capita income | 11th of 84 |
| Median home value | 29th of 84 |
| Bachelor's degree or higher | 31st of 84 |
| Median age | 1st of 84 |
| Owner-occupied share | 3rd of 84 |
The tracts next to it on St. Charles County's income ladder
| Tract | Rank | Median household income |
|---|---|---|
| Tract 3122.08 | 10th | $142,841±$8,438 · within the margin of this tract |
| Tract 3122.06 | 11th | $142,484±$10,671 · within the margin of this tract |
| Tract 3117.39 | 12th | $139,487±$24,787 · within the margin of this tract |
| Tract 3123 | 13th | $138,618±$23,635 |
| Tract 3111.51 | 14th | $136,818±$27,614 · within the margin of this tract |
| Tract 3111.48 | 15th | $134,815±$21,762 · within the margin of this tract |
| Tract 3111.54 | 16th | $133,013±$24,910 · within the margin of this tract |
"Within the margin": the two incomes differ by less than their combined 90% margins, so the survey cannot say which is higher and the ranks between them are not firm.
Source: PlainCities ranks computed from the American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) · How ranks are computed
How reliable are the figures for Census Tract 3123?
4 of the 17 figures for Census Tract 3123 on this page carry a coefficient of variation over 40% and are marked with a ring: they come from a small sample, so read them as rough.
A census tract's figures rest on a few hundred sampled households over five years, so its margins are wider than a city's. Two tracts differ only when the gap between them is larger than their combined 90% margin (the square root of the sum of the two squared margins). How to read a margin of error.
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026): margins of error as published · Check it at data.census.gov
How these figures are made: methodology and release checks · reading a margin of error · every state · corrections