City · Wisconsin
Colby, Wisconsin
Colby, city, mostly in Clark County (65.3% of its 2020 residents), with a part in Marathon County, Wisconsin. Colby had 1,957 residents on July 1, 2025 by the Census Bureau's estimate, down 1.9% since 2020; the 2020 Census counted 1,952 and the ACS 2020-2024 5-year estimates put it at 1,907 (±290). GEOID 5516150.
Residents, July 2025 estimate
1,957
Census Bureau estimate (no margin published)
2020 Census count: 1,952 · ACS 2020-2024: 1,907 ±290
Median household income
$50,114
±$13,210 (90% margin)
Wisconsin: $77,485
Median home value
$184,700
±$10,129 (90% margin)
Wisconsin: $266,500
Median gross rent
$854
±$66 (90% margin)
Wisconsin: $1,087
Where is Colby and what county is it in?
Colby is a city mostly in Clark County (65.3% of its 2020 residents), with a part in Marathon County, Wisconsin. It covers 1.6 square miles of land, 1,192 residents per square mile in 2020.
| County | 2020 residents | Share |
|---|---|---|
| Clark County | 1,275 | 65.3% |
| Marathon County | 677 | 34.7% |
Source: 2024 Gazetteer and 2020 place-by-county files, U.S. Census Bureau · Census reference files
How many people live in Colby, and is it growing?
The Census Bureau estimates that 1,957 people lived in Colby on July 1, 2025, down 1.9% since 2020, while Wisconsin grew 1.3%. The 2020 Census counted 1,952 residents. The 2020-2024 American Community Survey, a five-year sample, puts the population at 1,907 (±290).
| Measure | Colby | Clark County | Change since 2015-2019 |
|---|---|---|---|
| Total population | 1,907 ±290 | 34,739 | no clear change |
| Households | 689 ±74 | 12,839 | no clear change |
| Average household size | 2.59 ±0.29 | 2.67 | no clear change |
| Housing units | 713 ±75 | 14,961 | −142 |
Colby's population since 2000
From 1,616 in 2000 to 1,957 in 2025: up 21.1%. The 2000, 2010 and 2020 figures are census counts, each for Colby as it was drawn that year: a place that annexed land, or a community that has since incorporated, covered a different area then. The 2005 figure is the Census Bureau's intercensal estimate, revised to fit the 2000 and 2010 counts and drawn on 2010 boundaries; 2015 and 2025 are July 1 estimates made from the census before them.
Source: The 2000, 2010 and 2020 Census counts and the Census Bureau's population estimates (intercensal 2000-2010, Vintage 2020, Vintage 2025) · Census population estimates
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 Colby?
The median resident of Colby is 38.3 years old; 29.8% are under 18 and 22.3% are 65 or older. The largest group is non-Hispanic white residents at 71.5%, then Hispanic or Latino residents (of any race) at 25.4%. 12.3% of residents were born outside the United States.
| Measure | Colby | Clark County | Change since 2015-2019 |
|---|---|---|---|
| Median age | 38.3 ±2.2 | 36.7 | no clear change |
| Under 18 years | 29.8% ±5.1 pts | 29.7% | – |
| 65 years and over | 22.3% ±4.7 pts | 17.2% | – |
| Male | 50.1% ±4.9 pts | 51.1% | – |
| Hispanic or Latino (any race) | 25.4% ±10.0 pts | 6.4% | no clear change |
| White alone, not Hispanic | 71.5% ±9.9 pts | 90.5% | no clear change |
| Black or African American alone, not Hispanic | 0.0% ±1.2 pts | 0.3% | – |
| Asian alone, not Hispanic | 0.0% ±1.2 pts | 0.4% | – |
| American Indian and Alaska Native alone, not Hispanic | 0.0% ±1.2 pts | 0.1% | – |
| Native Hawaiian and Other Pacific Islander alone, not Hispanic | 0.0% ±1.2 pts | 0.0% | – |
| Two or more races, not Hispanic | 1.2% ±0.9 pts | 2.1% | – |
| Some other race alone, not Hispanic | 1.8% ±2.1 pts | 0.2% | – |
| Born outside the United States | 12.3% ±6.0 pts | 3.2% | no clear change |
| Speak a language other than English at home (age 5+) | 20.3% ±9.0 pts | 18.3% | – |
| Civilian veterans (age 18+) | 5.8% ±2.3 pts | 6.2% | – |
| With a disability | 15.3% ±5.7 pts | 11.9% | – |
| No health insurance coverage | 13.0% ±6.0 pts | 22.5% | no clear change |
| High school graduate or higher (age 25+) | 86.5% ±8.3 pts | 82.9% | – |
| Bachelor's degree or higher (age 25+) | 16.1% ±5.5 pts | 13.0% | +6.5 pts |
| Graduate or professional degree (age 25+) | 3.8% ±2.2 pts | 3.7% | – |
| Lived in the same house a year earlier | 88.2% ±5.5 pts | 90.3% | – |
| Moved from another state in the past year | 2.0% ±1.8 pts | 1.5% | – |
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 Colby earn?
Half of Colby's 689 households earn less than $50,114 a year (±$13,210), against $67,400 in Clark County and $77,485 in Wisconsin. In 2015-2019 it was $60,720 in 2024 dollars; the margins of error cannot tell the two periods apart. 19.1% of residents live below the poverty line.
| Measure | Colby | Clark County | Change since 2015-2019 |
|---|---|---|---|
| Median household income | $50,114 ±$13,210 | $67,400 | no clear change |
| Mean household income | $62,462 ±$7,249 | $87,875 | – |
| Per capita income | $24,388 ±$2,914 | $32,627 | no clear change |
| People below the poverty line | 19.1% ±7.2 pts | 12.1% | no clear change |
| Children under 18 below the poverty line | 16.4% ±12.6 pts | 16.0% | – |
| Households receiving SNAP | 23.2% ±7.6 pts | 10.5% | – |
| Households with a computer | 89.1% ±4.8 pts | 83.8% | – |
| Households with a broadband subscription | 84.5% ±5.6 pts | 78.6% | – |
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 Colby?
Owners occupy 53.4% of Colby's occupied homes and renters 46.6%. The median owner-occupied home is valued at $184,700 by its owner (±$10,129). The median renter pays $854 a month including utilities, and 35.8% of renters pay 35% or more of their income on rent.
| Measure | Colby | Clark County | Change since 2015-2019 |
|---|---|---|---|
| Median home value (owner-occupied) | $184,700 ±$10,129 | $172,800 | +$43,170 |
| Median gross rent | $854 ±$66 | $823 | no clear change |
| Renters paying 35% or more of income on rent | 35.8% ±11.6 pts | 22.9% | no clear change |
| Median monthly owner costs, with a mortgage | $1,399 ±$154 | $1,353 | – |
| Owner-occupied homes | 53.4% ±7.2 pts | 78.5% | −13.6 pts |
| Renter-occupied homes | 46.6% ±7.2 pts | 21.5% | – |
| Housing units | 713 ±75 | 14,961 | −142 |
| Homeowner vacancy rate | 4.6% ±6.5 pts | 0.9% | – |
| Rental vacancy rate | 0.0% ±6.8 pts | 5.8% | – |
| Single-family detached homes | 61.2% ±8.4 pts | 82.7% | – |
| Mobile homes | 4.8% ±3.9 pts | 6.6% | – |
| Built 2020 or later | 0.0% ±3.1 pts | 1.9% | – |
| Built 2010 to 2019 | 4.1% ±2.4 pts | 5.3% | – |
| Built 1939 or earlier | 14.4% ±6.0 pts | 24.8% | – |
| Households with no vehicle | 10.9% ±5.0 pts | 9.8% | – |
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 many new homes is Colby building?
Builders took permits for 0 new housing units in Colby in 2025 (0 in single-family houses), 0.0 per 1,000 residents against 4.3 across Wisconsin.
Counts of units in permits a local office issued; not every permitted unit is built. A year marked with months was reported for part of the year.
Source: Building Permits Survey, annual place files 2019-2025, U.S. Census Bureau · Census Building Permits Survey
How do people in Colby work and get to work?
79.5% of Colby's workers drive alone. The average trip to work takes 20.4 minutes.
| Measure | Colby | Clark County | Change since 2015-2019 |
|---|---|---|---|
| In the labor force (age 16+) | 52.9% ±6.0 pts | 64.3% | – |
| Unemployment rate | 1.4% ±1.3 pts | 3.7% | – |
| Drove alone to work | 79.5% ±6.8 pts | 69.0% | – |
| Carpooled | 6.5% ±4.1 pts | 9.3% | – |
| Public transportation | 0.0% ±2.9 pts | 0.1% | – |
| Walked | 3.7% ±2.2 pts | 5.7% | – |
| Worked from home | 7.2% ±5.4 pts | 12.4% | – |
| Mean travel time to work | 20.4 min ±3.3 | 22.2 min | no clear change |
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 Colby?
No census tract lies mostly in Colby; 2 tracts reach into it (2020 census blocks).
| Tract | Residents, 2020-2024 | Median household income |
|---|---|---|
| Tract 9501Clark County | 4,881 | $62,976 |
| Tract 22Marathon County | 3,455 | $67,000 |
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 Colby) · Census block assignment files
How does Colby compare with other places in Wisconsin?
By the Census Bureau's July 2025 estimates, Colby is the 7,770th-most populous of the 19,476 U.S. incorporated places that have one and the 266th-most populous of 608 in Wisconsin.
Colby ranks 888th of 914 places in Wisconsin with 1,000 or more residents and a reliable estimate, by median household income.
| Measure | Rank | Of |
|---|---|---|
| Population, July 2025 estimate | 266th | 608 |
| Growth 2020-2025 (PEP) | 782nd | 884 |
| Residents per square mile | 164th | 914 |
| Median household income | 888th | 914 |
| Per capita income | 902nd | 911 |
| Median home value | 773rd | 913 |
| Median gross rent | 625th | 825 |
| Poverty rate | 45th | 706 |
| Bachelor's degree or higher | 798th | 914 |
| Median age | 763rd | 914 |
| Owner-occupied share | 879th | 914 |
| Travel time to work | 693rd | 914 |
Colby's figures with every place in Wisconsin (CSV)
Every place in Wisconsin, sortable · Compare Colby 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 Colby?
15 of the 57 figures for Colby 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 Colby 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' public schools in Colby.