Boulder County Population

1870–2026

327.64K

2026 projection

1% since 2020 (decrease)

050K100K150K200K250K300K350K18801900192019401960198020002020

Source: U.S. Census Bureau decennial counts and annual estimates. 2026 is a projection. Values between recorded years are interpolated.

Use the left and right arrow keys to inspect population observations.

Population by year

Population estimates for Boulder County. Annual change is shown as a percentage. Growth is the total change since the preceding observation.
2026327,635-9250.28%
2025328,560-9250.28%
2024329,485+1,5400.47%
2023327,945+310.01%
2022327,914+5890.18%
2021327,325-3,6571.10%
2020330,982+4,9621.52%
2019326,020+5820.18%
2018325,438+2,4190.75%
2017323,019+1,2580.39%

Showing 10 of 30 years.

Boulder County Demographics

37.7median age

Median age

Female39 yrs
Male36.6 yrs

Adults

271,246
53,942 seniors (65+) · 20% of adults217,304 other adults

Sex

Female 49.6% · 163,111Male 50.4% · 165,850

Population by age

MaleFemale85+ years, male: 2,31185+ years, female: 4,07780–84 years, male: 2,51780–84 years, female: 3,10275–79 years, male: 4,17975–79 years, female: 4,71770–74 years, male: 6,99470–74 years, female: 8,22765–69 years, male: 8,84965–69 years, female: 8,96960–64 years, male: 9,61160–64 years, female: 9,64955–59 years, male: 9,88955–59 years, female: 10,29750–54 years, male: 10,62850–54 years, female: 10,25445–49 years, male: 10,13445–49 years, female: 10,02440–44 years, male: 10,28140–44 years, female: 10,51635–39 years, male: 11,12135–39 years, female: 9,66030–34 years, male: 11,71330–34 years, female: 10,25025–29 years, male: 12,24125–29 years, female: 10,41920–24 years, male: 17,57120–24 years, female: 15,93115–19 years, male: 14,45915–19 years, female: 14,45910–14 years, male: 8,93610–14 years, female: 8,5645–9 years, male: 7,9855–9 years, female: 7,6410–4 years, male: 6,4310–4 years, female: 6,35585+80–8475–7970–7465–6960–6455–5950–5445–4940–4435–3930–3425–2920–2415–1910–145–90–45K5K10K10K15K15K

Hover or tap an age group to see exact counts. Use the up and down arrow keys to inspect age groups.

U.S. Census Bureau, 2024 ACS 5-year estimates · Table S0101

Race and ethnicity

Tap a square or a group below to highlight it.

Each square is about 1% of residents (roughly 3,290 people).

Hispanic or Latino residents can be of any race. All other groups exclude Hispanic residents.

U.S. Census Bureau, 2024 ACS 5-year estimates · Table B03002

Boulder County Income

$103,994median household income

Median household income

$103,994

Half of households earn more, half earn less

Median earnings

$67,063

Typical yearly pay for a worker 25 or older.

Poverty rate

11.2%

About 1 in 9 residents

U.S. Census Bureau, 2024 ACS 5-year estimates · Tables S1901, S1501, S1701

Boulder County Marital Status

45% of residents age 15 and older are married.

MarriedNever married
Overall
Male
Female
Marital status of residents age 15 and older
StatusOverallMaleFemale
Married45%44%46%
Never married40%44%36%
Divorced11%9%12%
Widowed4%2%6%
Separated<1%<1%<1%

U.S. Census Bureau, 2024 ACS 5-year estimates · Table S1201

Sources

8 sources, all from the U.S. Census Bureau

Population

American Community Survey, 2024 5-year