Census-designated place · South Dakota
Lake Madison, South Dakota
Lake Madison, census-designated place, in Lake County, South Dakota. Lake Madison had 829 residents in the 2020 Census, a full count; the ACS 2020-2024 5-year estimates put it at 936 (±178). GEOID 4635430.
Residents, 2020 Census
829
Census count or controlled total
ACS 2020-2024 estimate: 936 ±178
Median household income
$129,191
±$49,280 (90% margin)
South Dakota: $75,081
Median home value
$477,800
±$73,199 (90% margin)
South Dakota: $257,400
Median gross rent
$867
±$455 (90% margin)
South Dakota: $946
Where is Lake Madison and what county is it in?
Lake Madison is a census-designated place: an unincorporated community the Census Bureau draws for counting, with no city government of its own, in Lake County, South Dakota. It covers 4.7 square miles of land, 176 residents per square mile in 2020.
Lake Madison lies mostly within Lake View Township and reaches into Wentworth Township and Chester Township (Lake County), towns or townships with their own local government (2020 census blocks).
Source: 2024 Gazetteer and 2020 place-by-county files, U.S. Census Bureau · Census reference files
How many people live in Lake Madison, and is it growing?
The 2020 Census counted 829 residents in Lake Madison, a full count rather than a sample. The 2020-2024 American Community Survey, a sample, estimates 936 (±178).
The Census Bureau publishes yearly population estimates for incorporated places only; Lake Madison is a census-designated place, so its figures come from the ACS and the 2020 Census.
| Measure | Lake Madison | Lake County | Change since 2015-2019 |
|---|---|---|---|
| Total population | 936 ±178 | 10,972 | no clear change |
| Households | 485 ±99 | 4,716 | no clear change |
| Average household size | 1.93 ±0.22 | 2.21 | no clear change |
| Housing units | 937 ±112 | 5,797 | no clear change |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026); Census PEP Vintage 2025 (SUB-EST2025, CO-EST2025); 2020 Census P.L. 94-171 · Check it at data.census.gov
Who lives in Lake Madison?
The median resident of Lake Madison is 63.2 years old; 10.5% are under 18 and 37.8% are 65 or older. The largest group is non-Hispanic white residents at 88.9%, then non-Hispanic American Indian and Alaska Native residents at 6.7%.
| Measure | Lake Madison | Lake County | Change since 2015-2019 |
|---|---|---|---|
| Median age | 63.2 ±3.3 | 43.8 | +4.5 |
| Under 18 years | 10.5% ±6.8 pts | 19.6% | – |
| 65 years and over | 37.8% ±8.3 pts | 24.3% | – |
| Male | 55.9% ±7.4 pts | 52.8% | – |
| Hispanic or Latino (any race) | 0.0% ±2.6 pts | 5.3% | – |
| White alone, not Hispanic | 88.9% ±10.2 pts | 88.8% | no clear change |
| Black or African American alone, not Hispanic | 0.0% ±2.6 pts | 0.7% | – |
| Asian alone, not Hispanic | 0.0% ±2.6 pts | 0.7% | – |
| American Indian and Alaska Native alone, not Hispanic | 6.7% ±9.6 pts | 2.5% | – |
| Native Hawaiian and Other Pacific Islander alone, not Hispanic | 0.0% ±2.6 pts | 0.2% | – |
| Two or more races, not Hispanic | 4.4% ±4.5 pts | 1.5% | – |
| Some other race alone, not Hispanic | 0.0% ±2.6 pts | 0.3% | – |
| Born outside the United States | 2.1% ±2.1 pts | 3.7% | – |
| Speak a language other than English at home (age 5+) | 1.0% ±1.5 pts | 5.0% | – |
| Civilian veterans (age 18+) | 9.5% ±5.5 pts | 7.8% | – |
| With a disability | 9.5% ±5.3 pts | 15.1% | – |
| No health insurance coverage | 1.0% ±1.7 pts | 4.0% | – |
| High school graduate or higher (age 25+) | 99.6% ±0.5 pts | 93.4% | – |
| Bachelor's degree or higher (age 25+) | 49.3% ±12.5 pts | 34.6% | no clear change |
| Graduate or professional degree (age 25+) | 18.3% ±7.0 pts | 9.8% | – |
| Lived in the same house a year earlier | 98.3% ±1.9 pts | 85.3% | – |
| Moved from another state in the past year | 0.7% ±1.4 pts | 4.5% | – |
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 Lake Madison earn?
Half of Lake Madison's 485 households earn less than $129,191 a year (±$49,280), against $76,808 in Lake County and $75,081 in South Dakota. In 2015-2019 it was $115,378 in 2024 dollars; the margins of error cannot tell the two periods apart.
| Measure | Lake Madison | Lake County | Change since 2015-2019 |
|---|---|---|---|
| Median household income | $129,191 ±$49,280 | $76,808 | no clear change |
| Mean household income | $236,969 ±$87,859 | $104,754 | – |
| Per capita income | $120,127 ±$48,025 | $45,963 | no clear change |
| People below the poverty line | 1.0% ±1.4 pts | 8.4% | – |
| Children under 18 below the poverty line | 0.0% ±22.3 pts | 14.8% | – |
| Households receiving SNAP | 3.3% ±5.7 pts | 5.2% | – |
| Households with a computer | 99.4% ±0.8 pts | 93.4% | – |
| Households with a broadband subscription | 97.1% ±2.7 pts | 86.6% | – |
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 Lake Madison?
Owners occupy 90.9% of Lake Madison's occupied homes and renters 9.1%. The median owner-occupied home is valued at $477,800 by its owner (±$73,199). The median renter pays $867 a month including utilities.
| Measure | Lake Madison | Lake County | Change since 2015-2019 |
|---|---|---|---|
| Median home value (owner-occupied) | $477,800 ±$73,199 | $247,600 | no clear change |
| Median gross rent | $867 ±$455 | $947 | no clear change |
| Renters paying 35% or more of income on rent | 6.8% ±12.2 pts | 37.4% | – |
| Median monthly owner costs, with a mortgage | $2,258 ±$275 | $1,586 | – |
| Owner-occupied homes | 90.9% ±5.7 pts | 73.8% | no clear change |
| Renter-occupied homes | 9.1% ±5.7 pts | 26.2% | – |
| Housing units | 937 ±112 | 5,797 | no clear change |
| Homeowner vacancy rate | 3.5% ±3.8 pts | 0.8% | – |
| Rental vacancy rate | 0.0% ±39.2 pts | 9.7% | – |
| Single-family detached homes | 72.9% ±9.7 pts | 73.7% | – |
| Mobile homes | 16.3% ±9.6 pts | 8.2% | – |
| Built 2020 or later | 5.8% ±5.3 pts | 1.9% | – |
| Built 2010 to 2019 | 16.2% ±7.0 pts | 9.3% | – |
| Built 1939 or earlier | 2.2% ±3.1 pts | 21.3% | – |
| Households with no vehicle | 0.8% ±1.2 pts | 3.5% | – |
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 Lake Madison work and get to work?
62.6% of Lake Madison's workers drive alone and 32.2% work from home. The average trip to work takes 17.1 minutes.
| Measure | Lake Madison | Lake County | Change since 2015-2019 |
|---|---|---|---|
| In the labor force (age 16+) | 60.6% ±8.8 pts | 65.4% | – |
| Unemployment rate | 2.9% ±3.5 pts | 3.0% | – |
| Drove alone to work | 62.6% ±13.0 pts | 77.9% | – |
| Carpooled | 2.3% ±2.7 pts | 5.9% | – |
| Public transportation | 0.0% ±5.0 pts | 0.9% | – |
| Walked | 1.0% ±1.7 pts | 3.8% | – |
| Worked from home | 32.2% ±13.0 pts | 10.5% | – |
| Mean travel time to work | 17.1 min ±6.7 | 14.9 min | −18.3 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
What census tracts are in Lake Madison?
No census tract lies mostly in Lake Madison; 1 tract reaches into it (2020 census blocks).
| Tract | Residents, 2020-2024 | Median household income |
|---|---|---|
| Tract 9603Lake County | 2,311 | $105,545 |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026); 2020 block assignment files (tract share = share of the tract's census blocks in Lake Madison) · Census block assignment files
How does Lake Madison compare with other places in South Dakota?
Lake Madison is not ranked by income or the other survey measures: those rankings include places of 1,000 or more residents (2020 Census) with a reliable estimate.
Lake Madison's figures with every place in South Dakota (CSV)
Every place in South Dakota, sortable · Compare Lake Madison with other places
Source: PlainCities ranks computed from the American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) and PEP Vintage 2025 · How ranks are computed
How reliable are the figures for Lake Madison?
24 of the 57 figures for Lake Madison 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.
The American Community Survey samples about one household in eight over five years, so every figure is an estimate with a 90% margin of error (shown under each value). A ring marks an estimate whose coefficient of variation is over 40%. A change is called only when the gap between the two periods is larger than their combined 90% margin (the square root of the sum of the two squared margins), the Census Bureau's test. 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 · ACS technical documentation
How these figures are made: methodology and release checks · reading a margin of error · every state · corrections
Not on this page: crime, weather and schools for Lake Madison are other agencies' records. Crime: the FBI's Crime Data Explorer · climate: NOAA's U.S. Climate Normals · schools: the National Center for Education Statistics' school search.