Census tract · Marathon County
Census Tract 21.01, Marathon County, Wisconsin
Census Tract 21.01, GEOID 55073002101, in Marathon County, Wisconsin, partly within Spencer, Brighton (town), Marathon County, Spencer (town), Unity and Marshfield. 4,370 residents in the ACS 2020-2024 5-year estimates (±302); the 2020 Census counted 4,349.
Residents, 2020-2024
4,370
±302 (90% margin)
2020 Census count: 4,349
Median household income
$79,762
±$7,904 (90% margin)
Marathon County: $77,884
Median home value
$185,400
±$15,334 (90% margin)
Marathon County: $219,600
Median gross rent
$672
±$125 (90% margin)
Marathon County: $999
Where is Census Tract 21.01?
Census Tract 21.01 is one of 32 census tracts in Marathon County, Wisconsin. It covers 66.44 square miles of land, 65 residents per square mile in 2020. Its GEOID, 55073002101, names it uniquely (how tract numbers and GEOIDs work).
| Place | Share of the tract |
|---|---|
| Spencer | 36% |
| Brighton (town), Marathon County | 29% |
| Spencer (town) | 25% |
| Unity | 8% |
| Marshfield | 1% |
5 census tracts border Census Tract 21.01: Tract 9505 in Clark County ($74,844), Tract 20 ($71,644), Tract 21.02 ($92,219), Tract 22 ($67,000) and Tract 107 in Wood County ($92,031). 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 21.01?
The 2020-2024 American Community Survey puts Census Tract 21.01's population at 4,370 (±302) in 1,706 households; the 2020 Census counted 4,349 residents and 1,823 housing units.
| Measure | Tract 21.01 | Marathon County |
|---|---|---|
| Total population | 4,370 ±302 | 138,403 |
| Households | 1,706 ±116 | 57,866 |
| Average household size | 2.55 ±0.09 | 2.36 |
| Housing units | 1,753 ±112 | 60,910 |
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 21.01?
The median resident of Census Tract 21.01 is 36.6 years old; 25.4% are under 18 and 15.0% are 65 or older. The largest group is non-Hispanic white residents at 94.7%, then Hispanic or Latino residents (of any race) at 3.0%.
| Measure | Tract 21.01 | Marathon County |
|---|---|---|
| Median age | 36.6 ±3.3 | 41.3 |
| Under 18 years | 25.4% ±2.5 pts | 22.5% |
| 65 years and over | 15.0% ±1.7 pts | 19.2% |
| Hispanic or Latino (any race) | 3.0% ±2.2 pts | 3.5% |
| White alone, not Hispanic | 94.7% ±2.4 pts | 86.2% |
| Black or African American alone, not Hispanic | 0.1% ±0.3 pts | 0.6% |
| Asian alone, not Hispanic | 0.4% ±0.6 pts | 5.7% |
| American Indian and Alaska Native alone, not Hispanic | 0.1% ±0.2 pts | 0.1% |
| Native Hawaiian and Other Pacific Islander alone, not Hispanic | 0.0% ±0.5 pts | 0.0% |
| Two or more races, not Hispanic | 1.6% ±0.6 pts | 3.6% |
| Some other race alone, not Hispanic | 0.0% ±0.5 pts | 0.3% |
| Born outside the United States | 2.5% ±1.9 pts | 4.3% |
| Speak a language other than English at home (age 5+) | 7.3% ±3.5 pts | 7.6% |
| Civilian veterans (age 18+) | 4.8% ±1.1 pts | 6.8% |
| With a disability | 11.0% ±2.2 pts | 12.8% |
| No health insurance coverage | 13.9% ±5.4 pts | 5.8% |
| High school graduate or higher (age 25+) | 84.6% ±5.1 pts | 93.3% |
| Bachelor's degree or higher (age 25+) | 16.3% ±2.8 pts | 28.1% |
| Graduate or professional degree (age 25+) | 4.3% ±1.3 pts | 8.4% |
| Lived in the same house a year earlier | 86.1% ±5.9 pts | 89.4% |
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 21.01 earn?
Half of the 1,706 households in Census Tract 21.01 earn less than $79,762 a year (±$7,904), against $77,884 across Marathon County: 16th highest of the county's 32 tracts with a reliable estimate. 4.5% of residents live below the poverty line.
| Measure | Tract 21.01 | Marathon County |
|---|---|---|
| Median household income | $79,762 ±$7,904 | $77,884 |
| Mean household income | $88,762 ±$4,792 | $97,899 |
| Per capita income | $34,767 ±$1,844 | $41,413 |
| People below the poverty line | 4.5% ±1.2 pts | 8.7% |
| Children under 18 below the poverty line | 2.4% ±2.2 pts | 11.1% |
| Households receiving SNAP | 9.8% ±4.7 pts | 9.9% |
| Households with a computer | 93.1% ±2.4 pts | 94.2% |
| Households with a broadband subscription | 88.3% ±3.1 pts | 90.0% |
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 21.01?
Owners occupy 79.2% of Census Tract 21.01's occupied homes and renters 20.8%. The median owner-occupied home is valued at $185,400 by its owner (±$15,334). The median renter pays $672 a month including utilities, and 24.5% of renters pay 35% or more of their income on rent.
| Measure | Tract 21.01 | Marathon County |
|---|---|---|
| Median home value (owner-occupied) | $185,400 ±$15,334 | $219,600 |
| Median gross rent | $672 ±$125 | $999 |
| Renters paying 35% or more of income on rent | 24.5% ±13.0 pts | 31.9% |
| Median monthly owner costs, with a mortgage | $1,435 ±$163 | $1,463 |
| Owner-occupied homes | 79.2% ±4.6 pts | 73.3% |
| Renter-occupied homes | 20.8% ±4.6 pts | 26.7% |
| Housing units | 1,753 ±112 | 60,910 |
| Single-family detached homes | 78.4% ±6.2 pts | 75.4% |
| Mobile homes | 8.0% ±3.3 pts | 2.5% |
| Built 2020 or later | 0.0% ±1.3 pts | 1.6% |
| Built 2010 to 2019 | 6.4% ±2.7 pts | 6.9% |
| Built 1939 or earlier | 18.5% ±5.4 pts | 16.5% |
| Households with no vehicle | 4.3% ±1.9 pts | 4.8% |
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 21.01 get to work?
72.7% of Census Tract 21.01's workers drive alone and 11.5% work from home. The average trip to work takes 19.5 minutes.
| Measure | Tract 21.01 | Marathon County |
|---|---|---|
| In the labor force (age 16+) | 70.9% ±3.4 pts | 66.9% |
| Unemployment rate | 1.8% ±1.2 pts | 2.9% |
| Drove alone to work | 72.7% ±3.4 pts | 76.2% |
| Carpooled | 9.2% ±2.8 pts | 7.5% |
| Public transportation | 0.0% ±1.0 pts | 0.2% |
| Walked | 4.2% ±2.1 pts | 1.9% |
| Worked from home | 11.5% ±2.6 pts | 12.9% |
| Mean travel time to work | 19.5 min ±2.9 | 19.1 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 21.01 compare with the other tracts in Marathon County?
Among Marathon County's tracts with a reliable estimate, Census Tract 21.01 ranks as shown below (1 = highest).
| Measure | In Marathon County |
|---|---|
| Population | 15th of 32 |
| Residents per square mile | 23rd of 32 |
| Median household income | 16th of 32 |
| Per capita income | 24th of 32 |
| Median home value | 23rd of 32 |
| Median gross rent | 32nd of 32 |
| Poverty rate | 20th of 28 |
| Bachelor's degree or higher | 29th of 32 |
| Median age | 29th of 32 |
| Owner-occupied share | 13th of 32 |
The tracts next to it on Marathon County's income ladder
| Tract | Rank | Median household income |
|---|---|---|
| Tract 19 | 13th | $85,139±$7,297 · within the margin of this tract |
| Tract 12.02 | 14th | $82,932±$11,226 · within the margin of this tract |
| Tract 2 | 15th | $80,461±$10,135 · within the margin of this tract |
| Tract 21.01 | 16th | $79,762±$7,904 |
| Tract 3 | 17th | $79,348±$13,228 · within the margin of this tract |
| Tract 11.05 | 18th | $73,750±$26,205 · within the margin of this tract |
| Tract 23.01 | 19th | $72,803±$8,635 · 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 21.01?
3 of the 18 figures for Census Tract 21.01 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