City · Colorado
Boulder, Colorado
Boulder, city, in Boulder County, Colorado. Boulder had 105,689 residents on July 1, 2025 by the Census Bureau's estimate, down 2.6% since 2020; the 2020 Census counted 108,250 and the ACS 2020-2024 5-year estimates put it at 106,433 (±77). GEOID 0807850.
Residents, July 2025 estimate
105,689
Census Bureau estimate (no margin published)
2020 Census count: 108,250 · ACS 2020-2024: 106,433 ±77
Median household income
$87,493
±$6,221 (90% margin)
Colorado: $95,470
Median home value
$1,039,500
±$40,565 (90% margin)
Colorado: $539,400
Median gross rent
$2,018
±$65 (90% margin)
Colorado: $1,761
Where is Boulder and what county is it in?
Boulder is a city in Boulder County, Colorado. It covers 26.9 square miles of land, 4,027 residents per square mile in 2020.
Boulder is in the Boulder, CO metropolitan statistical area (Census Bureau delineation, July 2023).
Source: 2024 Gazetteer and 2020 place-by-county files, U.S. Census Bureau · Census reference files
How many people live in Boulder, and is it growing?
The Census Bureau estimates that 105,689 people lived in Boulder on July 1, 2025, down 2.6% since 2020, while Colorado grew 4.1%. The 2020 Census counted 108,250 residents. The 2020-2024 American Community Survey, a five-year sample, puts the population at 106,433 (±77).
| Measure | Boulder | Boulder County | Change since 2015-2019 |
|---|---|---|---|
| Total population | 106,433 ±77 | 328,961 | no clear change |
| Households | 44,432 ±815 | 137,008 | +2,311 |
| Average household size | 2.12 ±0.04 | 2.30 | −0.15 |
| Housing units | 47,465 ±748 | 144,729 | +2,320 |
Boulder's population since 2000
From 94,673 in 2000 to 105,689 in 2025: up 11.6%. The 2000, 2010 and 2020 figures are census counts, each for Boulder 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 Boulder?
The median resident of Boulder is 28.8 years old; 11.8% are under 18 and 12.7% are 65 or older. The largest group is non-Hispanic white residents at 78.0%, then Hispanic or Latino residents (of any race) at 10.7%. 10.8% of residents were born outside the United States.
| Measure | Boulder | Boulder County | Change since 2015-2019 |
|---|---|---|---|
| Median age | 28.8 ±0.6 | 37.7 | no clear change |
| Under 18 years | 11.8% ±0.7 pts | 17.5% | – |
| 65 years and over | 12.7% ±0.6 pts | 16.4% | – |
| Male | 51.7% ±0.9 pts | 50.4% | – |
| Hispanic or Latino (any race) | 10.7% ±0.8 pts | 14.7% | no clear change |
| White alone, not Hispanic | 78.0% ±1.0 pts | 74.5% | −1.6 pts |
| Black or African American alone, not Hispanic | 1.0% ±0.2 pts | 0.8% | no clear change |
| Asian alone, not Hispanic | 5.4% ±0.5 pts | 4.7% | no clear change |
| American Indian and Alaska Native alone, not Hispanic | 0.2% ±0.1 pts | 0.2% | – |
| Native Hawaiian and Other Pacific Islander alone, not Hispanic | 0.0% ±0.1 pts | 0.1% | – |
| Two or more races, not Hispanic | 4.4% ±0.6 pts | 4.8% | – |
| Some other race alone, not Hispanic | 0.3% ±0.1 pts | 0.3% | – |
| Born outside the United States | 10.8% ±0.8 pts | 10.1% | no clear change |
| Speak a language other than English at home (age 5+) | 14.9% ±1.2 pts | 15.1% | – |
| Civilian veterans (age 18+) | 2.7% ±0.4 pts | 4.3% | – |
| With a disability | 7.6% ±0.7 pts | 9.4% | – |
| No health insurance coverage | 3.4% ±0.5 pts | 4.4% | no clear change |
| High school graduate or higher (age 25+) | 97.3% ±0.7 pts | 95.8% | – |
| Bachelor's degree or higher (age 25+) | 76.8% ±1.4 pts | 64.2% | no clear change |
| Graduate or professional degree (age 25+) | 40.4% ±1.7 pts | 30.0% | – |
| Lived in the same house a year earlier | 65.9% ±1.6 pts | 79.0% | – |
| Moved from another state in the past year | 9.1% ±1.0 pts | 5.1% | – |
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 Boulder earn?
Half of Boulder's 44,432 households earn less than $87,493 a year (±$6,221), against $103,994 in Boulder County and $95,470 in Colorado. In 2015-2019 it was $85,558 in 2024 dollars; the margins of error cannot tell the two periods apart. 21.5% of residents live below the poverty line.
| Measure | Boulder | Boulder County | Change since 2015-2019 |
|---|---|---|---|
| Median household income | $87,493 ±$6,221 | $103,994 | no clear change |
| Mean household income | $148,050 ±$8,886 | $148,847 | – |
| Per capita income | $63,074 ±$3,881 | $62,436 | +$7,764 |
| People below the poverty line | 21.5% ±1.4 pts | 11.2% | no clear change |
| Children under 18 below the poverty line | 9.1% ±2.7 pts | 7.0% | no clear change |
| Households receiving SNAP | 5.5% ±0.8 pts | 5.9% | – |
| Households with a computer | 99.0% ±0.3 pts | 98.3% | – |
| Households with a broadband subscription | 95.6% ±0.5 pts | 95.7% | – |
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 Boulder?
Owners occupy 47.2% of Boulder's occupied homes and renters 52.8%. The median owner-occupied home is valued at $1,039,500 by its owner (±$40,565). The median renter pays $2,018 a month including utilities, and 58.4% of renters pay 35% or more of their income on rent.
| Measure | Boulder | Boulder County | Change since 2015-2019 |
|---|---|---|---|
| Median home value (owner-occupied) | $1,039,500 ±$40,565 | $756,300 | +$178,014 |
| Median gross rent | $2,018 ±$65 | $1,966 | +$106 |
| Renters paying 35% or more of income on rent | 58.4% ±2.5 pts | 50.0% | +3.8 pts |
| Median monthly owner costs, with a mortgage | $3,210 ±$120 | $2,743 | – |
| Owner-occupied homes | 47.2% ±1.5 pts | 62.0% | no clear change |
| Renter-occupied homes | 52.8% ±1.5 pts | 38.0% | – |
| Housing units | 47,465 ±748 | 144,729 | +2,320 |
| Homeowner vacancy rate | 1.0% ±0.6 pts | 0.9% | – |
| Rental vacancy rate | 4.3% ±1.3 pts | 4.0% | – |
| Single-family detached homes | 38.7% ±1.3 pts | 57.2% | – |
| Mobile homes | 2.0% ±0.5 pts | 2.3% | – |
| Built 2020 or later | 1.4% ±0.4 pts | 2.0% | – |
| Built 2010 to 2019 | 8.1% ±0.9 pts | 11.4% | – |
| Built 1939 or earlier | 7.5% ±1.2 pts | 5.9% | – |
| Households with no vehicle | 9.1% ±1.2 pts | 5.2% | – |
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 Boulder building?
Builders took permits for 336 new housing units in Boulder in 2025 (31 in single-family houses), 3.2 per 1,000 residents against 5.6 across Colorado.
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 Boulder work and get to work?
39.1% of Boulder's workers drive alone and 34.4% work from home. The average trip to work takes 18.1 minutes. The unemployment rate in 2020-2024 averaged 6.0%.
| Measure | Boulder | Boulder County | Change since 2015-2019 |
|---|---|---|---|
| In the labor force (age 16+) | 63.7% ±1.3 pts | 66.9% | – |
| Unemployment rate | 6.0% ±0.9 pts | 4.8% | +1.4 pts |
| Drove alone to work | 39.1% ±1.7 pts | 52.8% | – |
| Carpooled | 3.2% ±0.6 pts | 5.3% | – |
| Public transportation | 5.1% ±0.9 pts | 2.6% | – |
| Walked | 9.5% ±1.2 pts | 4.0% | – |
| Worked from home | 34.4% ±1.9 pts | 31.2% | +19.9 pts |
| Mean travel time to work | 18.1 min ±0.6 | 22.3 min | −1.6 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 Boulder?
26 census tracts lie mostly in Boulder, and 8 more reach into it (2020 census blocks). Their median household incomes run from $23,590 (Tract 126.10) to $244,179 (Tract 121.01).
| Tract | Residents, 2020-2024 | Median household income |
|---|---|---|
| Tract 124.01Boulder County | 7,424 | $38,961 |
| Tract 123Boulder County | 7,025 | $33,750 |
| Tract 125.11Boulder County | 6,066 | $79,385 |
| Tract 121.05Boulder County | 6,180 | $102,112 |
| Tract 126.10Boulder County | 5,294 | $23,590 |
| Tract 122.07Boulder County | 4,899 | $77,965 |
| Tract 121.01Boulder County | 4,800 | $244,179 |
| Tract 121.07Boulder County | 4,377 | $99,948 |
| Tract 125.07Boulder County | 4,043 | $53,971 |
| Tract 125.05Boulder County | 4,100 | $184,353 |
| Tract 125.09Boulder County | 3,361 | $184,116 |
| Tract 122.04Boulder County | 3,346 | $51,583 |
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 Boulder) · Census block assignment files
How does Boulder compare with other places in Colorado?
By the Census Bureau's July 2025 estimates, Boulder is the 311th-most populous of the 19,476 U.S. incorporated places that have one and the 12th-most populous of 272 in Colorado.
Boulder ranks 113th of 218 places in Colorado with 1,000 or more residents and a reliable estimate, by median household income.
| Measure | Rank | Of |
|---|---|---|
| Population, July 2025 estimate | 12th | 272 |
| Growth 2020-2025 (PEP) | 124th | 150 |
| Residents per square mile | 21st | 221 |
| Median household income | 113th | 218 |
| Per capita income | 56th | 220 |
| Median home value | 12th | 217 |
| Median gross rent | 46th | 200 |
| Poverty rate | 14th | 151 |
| Bachelor's degree or higher | 9th | 216 |
| Median age | 213th | 220 |
| Owner-occupied share | 207th | 218 |
| Work from home | 17th | 176 |
| Travel time to work | 178th | 221 |
Boulder's figures with every place in Colorado (CSV)
Every place in Colorado, sortable · Compare Boulder 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 Boulder?
1 of the 57 figures for Boulder on this page carries a coefficient of variation over 40% and is 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 Boulder 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 Boulder.