Longmont, Colorado demographics

Longmont, CO demographics: median age 40.3; 47.0% of adults 25+ hold a bachelor’s degree. Age, race, households, languages and education, ACS 2020–2024 with margins of error.

ACS 2020–2024 · Longmont city, Colorado · Incorporated city · GEOID 0845970. The survey estimates a population of 99,406 for its five-year window. This is separate from the annual July 2025 population estimate on the city overview.

Median age in Longmont is 40.3 years, with a 90% margin of error of 0.7 years. There are 42,155 households (±872). Age and household distributions show how these totals are composed; they do not establish which neighborhood suits a particular person.

Every count and share is an estimate. “±” is a 90% margin of error (MOE); pp means percentage points. Derived shares use the category count divided by the named universe. Aggregated category MOEs and percentage MOEs are approximate. A margin larger than half its estimate is flagged as low precision. Blank source uncertainty is shown as unavailable, never zero.

Age distribution and sex

City, state and U.S. estimates · ACS 2020–2024
Measure / survey universe	City estimate ± MOE	State estimate ± MOE	U.S. estimate ± MOE
Median age Total population · years	40.3 ±0.7	37.7 ±0.1	38.9 ±0.1

Age groups · B01001 · ACS 2020–2024 Total population: 99,406
Category	Count ± MOE	Share ± MOE (pp)	Colorado	U.S.
Under 18	18,724 ±969	18.8% ±1.0 pp	21.0%	22.0%
18–34	23,499 ±1,259	23.6% ±1.3 pp	24.8%	22.8%
35–64	38,663 ±1,413	38.9% ±1.4 pp	38.6%	38.0%
65 and older	18,520 ±1,036	18.6% ±1.0 pp	15.6%	17.2%

Sex categories as published by ACS · B01001 · ACS 2020–2024 Total population: 99,406
Category	Count ± MOE	Share ± MOE (pp)	Colorado	U.S.
Male	49,392 ±945	49.7% ±0.9 pp	50.7%	49.5%
Female	50,014 ±961	50.3% ±0.9 pp	49.3%	50.5%

The age groups are mutually exclusive and cover the entire population. The sex categories follow this ACS table’s published classification; they are not a survey of gender identity.

Race and Hispanic origin

Race · B02001 · ACS 2020–2024 Total population: 99,406
Category	Count ± MOE	Share ± MOE (pp)	Colorado	U.S.
White alone	71,774 ±2,080	72.2% ±2.1 pp	70.5%	61.0%
Black or African American alone	869 ±255	0.9% ±0.3 pp	4.0%	12.2%
American Indian and Alaska Native alone	580 ±190	0.6% ±0.2 pp	1.1%	0.9%
Asian alone	3,371 ±703	3.4% ±0.7 pp	3.3%	6.0%
Native Hawaiian and Other Pacific Islander alone	96 ±68 · low precision	0.1% ±0.1 pp · low precision	0.2%	0.2%
Some other race alone	5,758 ±1,190	5.8% ±1.2 pp	6.0%	7.1%
Two or more races	16,958 ±1,799	17.1% ±1.8 pp	14.9%	12.6%

Hispanic or Latino origin · B03003 · ACS 2020–2024 Total population: 99,406
Category	Count ± MOE	Share ± MOE (pp)	Colorado	U.S.
Not Hispanic or Latino	75,558 ±1,441	76.0% ±1.4 pp	77.5%	80.7%
Hispanic or Latino	23,848 ±1,371	24.0% ±1.4 pp	22.5%	19.3%

Hispanic origin and race are separate questions. People of Hispanic or Latino origin may be of any race and appear in both tables. Do not add the Hispanic share to race shares. Race alone and two-or-more-race groups are the mutually exclusive categories of the race table.

Household types, children and living alone

Household types · B11001 · ACS 2020–2024 Households: 42,155
Category	Count ± MOE	Share ± MOE (pp)	Colorado	U.S.
Married-couple family	18,480 ±799	43.8% ±1.7 pp	48.3%	46.9%
Other family: male householder, no spouse present	2,171 ±374	5.2% ±0.9 pp	4.5%	5.1%
Other family: female householder, no spouse present	3,838 ±517	9.1% ±1.2 pp	8.9%	12.2%
Nonfamily: householder living alone	12,756 ±873	30.3% ±2.0 pp	28.6%	28.7%
Nonfamily: householder not living alone	4,910 ±597	11.6% ±1.4 pp	9.7%	7.0%

Households with children · B11005 · ACS 2020–2024 Households: 42,155
Category	Count ± MOE	Share ± MOE (pp)	Colorado	U.S.
Households with people under 18	10,389 ±661	24.6% ±1.5 pp	28.4%	29.5%
Households without people under 18	31,766 ±1,212	75.4% ±2.4 pp	71.6%	70.5%

Household size · B11016 · ACS 2020–2024 Households: 42,155
Category	Count ± MOE	Share ± MOE (pp)	Colorado	U.S.
One-person nonfamily households	12,756 ±873	30.3% ±2.0 pp	28.6%	28.7%
Two-person households	15,560 ±987	36.9% ±2.2 pp	36.0%	33.8%
Three-person households	6,080 ±611	14.4% ±1.4 pp	14.8%	15.3%
Four-person households	4,733 ±482	11.2% ±1.1 pp	12.3%	12.6%
Five-person households	1,764 ±311	4.2% ±0.7 pp	5.1%	5.9%
Six-person households	856 ±352	2.0% ±0.8 pp	2.0%	2.2%
Seven or more people	406 ±163	1.0% ±0.4 pp	1.1%	1.4%

A family household contains related people under the Census definition. A nonfamily household can contain one person or unrelated people sharing a home. Households with children can also appear in the household-type and size tables, so those tables must not be added together. Household estimates exclude people living in group quarters from the household universe.

Nativity and languages spoken at home

Nativity · B05002 · ACS 2020–2024 Total population: 99,406
Category	Count ± MOE	Share ± MOE (pp)	Colorado	U.S.
Native	89,398 ±1,124	89.9% ±1.1 pp	90.2%	85.9%
Foreign born	10,008 ±1,024	10.1% ±1.0 pp	9.8%	14.1%

Language spoken at home · C16001 · ACS 2020–2024 Population age 5 and older: 94,599
Category	Count ± MOE	Share ± MOE (pp)	Colorado	U.S.
English only	77,303 ±1,646	81.7% ±1.7 pp	83.8%	77.7%
Spanish	12,820 ±1,356	13.6% ±1.4 pp	11.1%	13.6%
French, Haitian, or Cajun	311 ±193 · low precision	0.3% ±0.2 pp · low precision	0.4%	0.7%
German or other West Germanic	519 ±189	0.5% ±0.2 pp	0.4%	0.5%
Russian, Polish, or other Slavic	680 ±360 · low precision	0.7% ±0.4 pp · low precision	0.6%	0.7%
Other Indo-European	815 ±315	0.9% ±0.3 pp	1.0%	2.0%
Korean	22 ±44 · low precision	0.0% ±0.0 pp · low precision	0.2%	0.3%
Chinese, including Mandarin and Cantonese	636 ±217	0.7% ±0.2 pp	0.5%	1.1%
Vietnamese	104 ±113 · low precision	0.1% ±0.1 pp · low precision	0.4%	0.5%
Tagalog, including Filipino	134 ±103 · low precision	0.1% ±0.1 pp · low precision	0.2%	0.6%
Other Asian and Pacific Island	869 ±416	0.9% ±0.4 pp	0.6%	1.1%
Arabic	70 ±64 · low precision	0.1% ±0.1 pp · low precision	0.2%	0.5%
Other and unspecified	316 ±254 · low precision	0.3% ±0.3 pp · low precision	0.7%	0.8%

Foreign born means not a U.S. citizen at birth; it includes naturalized citizens. Language categories describe speech at home among people age five and older. A language other than English at home does not establish that someone cannot speak English. This city page uses the published C16001 summary categories because the more detailed B16001 table does not provide these city records in this release.

Educational attainment

Highest completed education · B15003 · ACS 2020–2024 Population age 25 and older: 71,468
Category	Count ± MOE	Share ± MOE (pp)	Colorado	U.S.
Less than high school graduate	5,305 ±734	7.4% ±1.0 pp	7.1%	10.4%
High school graduate or equivalency	12,643 ±973	17.7% ±1.3 pp	19.7%	26.0%
Some college, no degree	14,462 ±991	20.2% ±1.3 pp	19.2%	19.1%
Associate’s degree	5,491 ±539	7.7% ±0.7 pp	8.3%	8.8%
Bachelor’s degree	20,069 ±991	28.1% ±1.3 pp	28.1%	21.6%
Graduate or professional degree	13,498 ±872	18.9% ±1.2 pp	17.6%	14.1%

The denominator excludes residents under 25. Each person is counted in the highest attainment category they completed. This table does not measure the quality of local schools or the education level of every current student.

Residence one year earlier

Geographic mobility · B07003 · ACS 2020–2024 Population age 1 and older: 98,822
Category	Count ± MOE	Share ± MOE (pp)	Colorado	U.S.
Same house	82,469 ±1,739	83.5% ±1.7 pp	84.1%	87.7%
Moved within same county	6,994 ±1,431	7.1% ±1.4 pp	6.7%	6.3%
Moved from a different county in the same state	5,426 ±946	5.5% ±1.0 pp	4.8%	3.1%
Moved from a different state	3,577 ±687	3.6% ±0.7 pp	3.8%	2.3%
Moved from abroad	356 ±200 · low precision	0.4% ±0.2 pp · low precision	0.6%	0.6%

These are respondents’ residence patterns one year before their survey response, pooled across the five-year window. They are not a net migration count for 2025. A person can move to a different house within the same city or county; moves within the same county should not automatically be interpreted as new arrivals to the city.

Health insurance, internet access and veterans

7.2% of Longmont residents (±0.8 percentage points) had no health insurance coverage when surveyed, compared with 7.7% in Colorado and 8.4% nationally. 94.9% of households subscribe to broadband of any type, including cellular data plans. A subscription is not the same as available service: the FCC National Broadband Map shows providers at a specific address.

City, state and U.S. shares · ACS 2020–2024
Measure	Longmont	Colorado	U.S.	Compared with Colorado
People without health insurance Civilian noninstitutionalized population	7.2% ±0.8 pp	7.7%	8.4%	Not statistically different
Households with a broadband subscription Households	94.9% ±1.0 pp	93.5%	91.0%	Higher
Veterans Civilian population age 18 and older	6.2% ±0.6 pp	7.5%	6.2%	Lower

Reading and reusing the estimates

The Census table links above lead to the original detailed tables. Counts, source universes and uncertainty are retained in the source observation download for Longmont . Compare these figures with the same survey window; do not compare one city’s five-year estimate with another city’s annual estimate as though they measured the same period. For methods, see uncertainty and denominator calculations.

Read Longmont housing and cost context or return to the city profile.