Census tract · Boulder County

Census Tract 125.09, Boulder County, Colorado

Census Tract 125.09, GEOID 08013012509, in Boulder County, Colorado, entirely within Boulder. 3,361 residents in the ACS 2020-2024 5-year estimates (±468); the 2020 Census counted 3,322.

Residents, 2020-2024

3,361

±468 (90% margin)
2020 Census count: 3,322

Median household income

$184,116

±$14,616 (90% margin)
Boulder County: $103,994

Median home value

$1,146,300

±$29,910 (90% margin)
Boulder County: $756,300

Median gross rent

$3,500 or more

The survey's top or bottom value; no margin is published
Boulder County: $1,966

Where is Census Tract 125.09?

Census Tract 125.09 is one of 78 census tracts in Boulder County, Colorado. It covers 0.68 square miles of land, 4,878 residents per square mile in 2020. Its GEOID, 08013012509, names it uniquely (how tract numbers and GEOIDs work).

Places Census Tract 125.09 lies in (share of its 2020 census blocks)
PlaceShare of the tract
Boulder100%
Census Tract 125.09 (marked with a dot) in Boulder County, Colorado. Boundaries: Census Bureau 2024.
125.05125.08125.10 125.09 1 mi
Census Tract 125.09 (shaded) and the tracts that border it, numbered. Boundaries: Census Bureau 2024 cartographic boundary file, 1:500,000.

3 census tracts border Census Tract 125.09: Tract 125.05 ($184,353), Tract 125.08 ($97,019) and Tract 125.10 ($145,625). 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 125.09?

The 2020-2024 American Community Survey puts Census Tract 125.09's population at 3,361 (±468) in 1,185 households; the 2020 Census counted 3,322 residents and 1,314 housing units.

Counts, ACS 2020-2024 5-year estimates
Measure Tract 125.09BoulderBoulder CountyColorado
Total population 3,361 ±468 106,433 328,961 5,862,189
Households 1,185 ±129 44,432 137,008 2,374,218
Average household size 2.80 ±0.20 2.12 2.30 2.42
Housing units 1,290 ±123 47,465 144,729 2,589,053

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 125.09?

The median resident of Census Tract 125.09 is 43.5 years old; 29.6% are under 18 and 17.6% are 65 or older. The largest group is non-Hispanic white residents at 89.3%, then Hispanic or Latino residents (of any race) at 3.7%. 11.0% of residents were born outside the United States.

Age, origin, education, ACS 2020-2024 5-year estimates. Race groups are non-Hispanic; Hispanic includes any race.
Measure Tract 125.09BoulderBoulder CountyColorado
Median age 43.5 ±2.0 28.8 37.7 37.7
Under 18 years 29.6% ±4.1 pts 11.8% 17.5% 21.0%
65 years and over 17.6% ±3.5 pts 12.7% 16.4% 15.6%
Hispanic or Latino (any race) 3.7% ±2.2 pts 10.7% 14.7% 22.5%
White alone, not Hispanic 89.3% ±4.7 pts 78.0% 74.5% 64.8%
Black or African American alone, not Hispanic 1.1% ±1.1 pts 1.0% 0.8% 3.8%
Asian alone, not Hispanic 3.4% ±3.0 pts 5.4% 4.7% 3.2%
American Indian and Alaska Native alone, not Hispanic 0.0% ±1.3 pts 0.2% 0.2% 0.4%
Native Hawaiian and Other Pacific Islander alone, not Hispanic 0.0% ±1.3 pts 0.0% 0.1% 0.1%
Two or more races, not Hispanic 2.6% ±1.7 pts 4.4% 4.8% 4.6%
Some other race alone, not Hispanic 0.0% ±1.3 pts 0.3% 0.3% 0.5%
Born outside the United States 11.0% ±4.0 pts 10.8% 10.1% 9.8%
Speak a language other than English at home (age 5+) 13.4% ±6.2 pts 14.9% 15.1% 16.2%
Civilian veterans (age 18+) 4.9% ±2.4 pts 2.7% 4.3% 7.5%
With a disability 8.6% ±2.6 pts 7.6% 9.4% 11.4%
No health insurance coverage 1.6% ±1.2 pts 3.4% 4.4% 7.7%
High school graduate or higher (age 25+) 98.8% ±1.0 pts 97.3% 95.8% 92.9%
Bachelor's degree or higher (age 25+) 80.1% ±6.4 pts 76.8% 64.2% 45.7%
Graduate or professional degree (age 25+) 46.7% ±7.2 pts 40.4% 30.0% 17.6%
Lived in the same house a year earlier 89.6% ±4.4 pts 65.9% 79.0% 84.1%

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 Census Tract 125.09 earn?

Half of the 1,185 households in Census Tract 125.09 earn less than $184,116 a year (±$14,616), against $103,994 across Boulder County: 6th highest of the county's 76 tracts with a reliable estimate. 4.5% of residents live below the poverty line.

Income and poverty in 2024 dollars, ACS 2020-2024 5-year estimates
Measure Tract 125.09BoulderBoulder CountyColorado
Median household income $184,116 ±$14,616 $87,493 $103,994 $95,470
Mean household income $242,865 ±$31,700 $148,050 $148,847 $128,255
Per capita income $86,305 ±$10,976 $63,074 $62,436 $52,636
People below the poverty line 4.5% ±2.9 pts 21.5% 11.2% 9.4%
Children under 18 below the poverty line 2.2% ±2.9 pts 9.1% 7.0% 11.1%
Households receiving SNAP 1.9% ±2.0 pts 5.5% 5.9% 8.5%
Households with a computer 97.0% ±2.7 pts 99.0% 98.3% 97.2%
Households with a broadband subscription 97.1% ±2.3 pts 95.6% 95.7% 93.5%

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 125.09?

Owners occupy 82.2% of Census Tract 125.09's occupied homes and renters 17.8%. The median owner-occupied home is valued at $1,146,300 by its owner (±$29,910). The median renter pays $3,500 or more a month including utilities, and 29.4% of renters pay 35% or more of their income on rent.

Housing, ACS 2020-2024 5-year estimates
Measure Tract 125.09BoulderBoulder CountyColorado
Median home value (owner-occupied) $1,146,300 ±$29,910 $1,039,500 $756,300 $539,400
Median gross rent $3,500 or more $2,018 $1,966 $1,761
Renters paying 35% or more of income on rent 29.4% ±16.5 pts 58.4% 50.0% 42.7%
Median monthly owner costs, with a mortgage $3,218 ±$287 $3,210 $2,743 $2,326
Owner-occupied homes 82.2% ±6.7 pts 47.2% 62.0% 66.2%
Renter-occupied homes 17.8% ±6.7 pts 52.8% 38.0% 33.8%
Housing units 1,290 ±123 47,465 144,729 2,589,053
Single-family detached homes 93.3% ±3.5 pts 38.7% 57.2% 61.4%
Mobile homes 0.0% ±3.2 pts 2.0% 2.3% 3.5%
Built 2020 or later 0.0% ±3.2 pts 1.4% 2.0% 3.0%
Built 2010 to 2019 0.0% ±3.2 pts 8.1% 11.4% 12.8%
Built 1939 or earlier 0.0% ±3.2 pts 7.5% 5.9% 7.0%
Households with no vehicle 4.1% ±2.7 pts 9.1% 5.2% 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 do people in Census Tract 125.09 get to work?

26.5% of Census Tract 125.09's workers drive alone and 51.5% work from home. The average trip to work takes 20.5 minutes.

Work and commuting, ACS 2020-2024 5-year estimates
Measure Tract 125.09BoulderBoulder CountyColorado
In the labor force (age 16+) 61.7% ±6.1 pts 63.7% 66.9% 68.6%
Unemployment rate 1.8% ±1.6 pts 6.0% 4.8% 4.6%
Drove alone to work 26.5% ±6.8 pts 39.1% 52.8% 65.1%
Carpooled 3.9% ±3.1 pts 3.2% 5.3% 7.7%
Public transportation 5.5% ±2.9 pts 5.1% 2.6% 1.6%
Walked 3.2% ±3.1 pts 9.5% 4.0% 2.5%
Worked from home 51.5% ±8.5 pts 34.4% 31.2% 21.0%
Mean travel time to work 20.5 min ±3.7 18.1 min 22.3 min 25.2 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 125.09 compare with the other tracts in Boulder County?

Among Boulder County's tracts with a reliable estimate, Census Tract 125.09 ranks as shown below (1 = highest).

Census Tract 125.09's rank among the tracts of Boulder County and of Boulder
MeasureIn Boulder CountyIn Boulder
Population51st of 7817th of 30
Residents per square mile23rd of 7816th of 30
Median household income6th of 763rd of 29
Per capita income14th of 789th of 30
Median home value11th of 759th of 29
Median gross rent1st of 761st of 29
Poverty rate50th of 5726th of 26
Bachelor's degree or higher14th of 7811th of 30
Median age30th of 787th of 30
Owner-occupied share16th of 763rd of 28

The tracts next to it on Boulder County's income ladder

Median household income, ACS 2020-2024 5-year estimates
TractRankMedian household incomeResidents
Tract 6143rd$201,288±$28,479 · within the margin of this tract4,120
Tract 130.044th$201,146±$32,269 · within the margin of this tract3,428
Tract 125.055th$184,353±$44,030 · within the margin of this tract4,100
Tract 125.096th$184,116±$14,6163,361
Tract 130.067th$180,819±$36,650 · within the margin of this tract5,785
Tract 128.028th$180,234±$32,553 · within the margin of this tract7,068
Tract 129.039th$168,500±$38,120 · within the margin of this tract2,331

"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 125.09?

2 of the 18 figures for Census Tract 125.09 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