Longmont, Colorado population is 100,109 as of July 1, 2025 (U.S. Census Bureau Vintage 2025 estimate), ranking #343 nationally and #13 in Colorado. Cost of living runs 5.2% above the U.S. average (BEA RPP 2024); a family of four needs roughly $122,585/yr to break even (2025 modeled). This profile draws on 13 federal datasets covering population, housing, income, employment, climate, and risk.
At a glance.
2025 population
100,109
+509 in the last year
Top 2% of 19,483 U.S. cities
Census Vintage 2025
Cost of living
RPP 105.2
+5.2% vs US
Boulder, CO metro · BEA 2024
Family-of-4 budget
$122,585/yr
+53% vs US
Modeled 2025 · federal sources
Median HH income
$90,671
+17% vs US
ACS 2020–2024 5-yr
Median home value
$572,800
+89% vs US
ACS 2020–2024 5-yr
2-BR fair-market rent
$2,124/mo
HUD FY2026 · 40th pct
Avg July high
90°F
NOAA 1991–2020
Gigabit broadband
99%
ISP-reported, FCC BDC
Explore Longmont, CO demographics, including age, race and ethnicity, households, origins, language, and education.
How many people live in Longmont?
100,109 people live in Longmont as of July 1, 2025 (U.S. Census Bureau Population Estimates Program, Vintage 2025), the #343 largest U.S. city.
How big is Longmont?
Longmont covers 29.3 square miles of land and 2.0 square miles of water. Its population density is about 3,419 residents per square mile of land. Compare U.S. cities by land area →
Source detail: 2025 population
2025 population
Source agency
U.S. Census Bureau, Population Division
Dataset
Census PEP
Vintage / period
Vintage 2025 (Jul 1, 2025)
Native geography
Census PEP subcounty place records for the included city universe.
Transformation
Copied from POPESTIMATE2025, joined by Census GEOID, and used for ranks, filters, and city pages.
Known limit: Annual estimate, not a decennial count; each new PEP vintage can revise the prior series.
Population grew 1.2% from the April 2020 base to mid-2025.
Vintage 2025 · annual estimates
Recent history (V2025 series, 2020 base → 2025).
2020 base: 98,900 → 2025: 100,109 (+1.2%)
Year
Population
Reference date
2020 base
98,900
April 1, 2020
2020
99,192
July 1, 2020
2021
99,762
July 1, 2021
2022
98,988
July 1, 2022
2023
98,990
July 1, 2023
2024
99,600
July 1, 2024
2025
100,109
July 1, 2025
Earlier history (2010–2019, prior Census vintage)
These figures come from the U.S. Census Bureau’s Vintage 2019 release — a separate, earlier methodology. They’re shown here as historical context only; the 2010 and 2019 values aren’t directly comparable to the 2020–2025 series above.
Population grew 12.5% from the July 2010 estimate to 2019 (V2019 — see seam note below).
Longmont is the #343 largest of 19,483 U.S. cities and #13 in Colorado.
▸Show the analyst detail (9 rows)
Measure
Value
Note
2020 base
98,900
April 1, 2020 census base
5-yr change
+1,209
2020 base → 2025; within V2025
5-yr change %
+1.2%
within V2025 only
1-yr change
+509
2024 → 2025 estimate
1-yr change %
+0.5%
within V2025 only
Density
3,419
people per sq mi, land only
Land area
29.3
sq mi (2025 Gazetteer)
U.S. rank by population
#343
of 19,483 cities
State rank by population
#13
of 272 in Colorado
What is the median household income in Longmont?
Median household income is 17% above the U.S. median ($90,671 vs $77,719); 8.6% live in poverty — 3.9 points below the 12.5% U.S. rate.
Median household income$90,671
US
Longmont: $90,671 — 17% above the US median of $77,719.
Scale: 10th–90th percentile of cities with ACS income data
Longmont
$90,671
United States
$77,719
Income and poverty estimates for Longmont from the U.S. Census Bureau's American Community Survey (ACS) 5-Year estimates (window 2020–2024). Every figure is shown with its 90% margin of error (MOE). Cells where the ± margin exceeds half the estimate are flagged "low precision." See methodology §12.
Measure
Estimate
± margin / note
Median household income
90,671+16.7% vs US
±2,975
Per capita income
49,333+14.0% vs US
±1,723
Population in poverty
8.6%
share of population for whom poverty status is determined
Median home value is 89% above the U.S. median ($572,800 vs $303,400); median rent is 35% above ($1,816 vs $1,348); price-to-income ratio is 6.3×, making it 1.6× as cost-burdened as the typical U.S. city (3.9×).
Median home value$572,800
US
Longmont: $572,800 — 89% above the US median of $303,400.
Scale: 10th–90th percentile of cities with ACS home-value data
HUD 2-BR fair-market rent$2,124/mo
US
Longmont: $2,124/mo — 97% above the US median of $1,077/mo.
Scale: 10th–90th percentile of cities with a HUD Fair Market Rent
Poverty (Census SAIPE 2024, model-based), unemployment (BLS LAUS 2024 annual averages), and remote-work share (ACS 2020–2024) for Longmont. Numbers are labeled at their native grain — place-grain when BLS publishes it, otherwise per-county. We do not compute population-weighted county averages. See methodology §13.
Measure
Value
Grain
Unemployment rate (annual avg)
4.2%
Longmont (BLS sub-state LAUS)
Civilian labor force
58,375
2024 annual avg
Worked from home
22.3%+59.1% vs US
share of workers 16+ commuting from home · U.S. median: 14% · ACS
County context — Longmont spans 2 counties; all are listed (no weighted average):
County
Poverty rate
Median HH income
Unemployment
Boulder County
10.6%
$103,293
4.2%
Weld County
9.6%
$100,638
4.5%
Top industries by private employment — NAICS supersectors rolled up from Longmont's linked 2 counties in the U.S. Bureau of Labor Statistics' Quarterly Census of Employment and Wages (QCEW, 2024 annual averages). See methodology §11.
#
Industry (NAICS supersector)
Private employment
Avg weekly wage
#1
Professional and technical services (54)
38,855
$2,953 / wk
#2
Manufacturing (31-33)
34,794
$1,703 / wk
#3
Health care and social assistance (62)
33,743
$1,270 / wk
#4
Retail trade (44-45)
27,907
$852 / wk
#5
Accommodation and food services (72)
26,407
$559 / wk
What workers earn in the Boulder, CO metro — top occupations by employment plus six curated benchmarks (registered nurse, software developer, elementary teacher, general manager, retail salesperson, truck driver). Wages are metro-area medians from the U.S. Bureau of Labor Statistics' Occupational Employment and Wage Statistics (May 2025). See methodology §25.
Software Developers is the largest tracked occupation in the Boulder, CO metro (7,130 jobs, median $164,560/yr).
▸Show all 12 occupations
Occupation
Employment
Median annual
Median hourly
Fast Food and Counter Workers
4,880
$36,190
$17.40
Business Operations Specialists, All Other
3,610
$94,040
$45.21
Sales Representatives of Services, Except Advertising, Insurance, Financial Services, and Travel
3,230
$99,990
$48.07
Market Research Analysts and Marketing Specialists
3,130
$97,600
$46.93
Cashiers
3,100
$38,520
$18.52
Project Management Specialists
2,920
$122,040
$58.67
Software Developers · benchmark
7,130
$164,560
$79.11
Retail Salespersons · benchmark
4,880
$38,700
$18.61
Registered Nurses · benchmark
3,140
$103,290
$49.66
General and Operations Managers · benchmark
2,750
$152,100
$73.13
Elementary School Teachers, Except Special Education · benchmark
1,630
$80,640
—
Heavy and Tractor-Trailer Truck Drivers · benchmark
650
$63,810
$30.68
This city spans multiple metros; OEWS data shown is for Boulder, CO, the metro of the city's primary county.
All items run 5.2% above the U.S. average (RPP 105.2); rents run 57.0% above (RPP 157.0) — the metro's housing premium is the main driver.
Cost of living (RPP, all items)RPP 105.2
US
Longmont's cost of living runs 5.2% above the U.S. average (RPP 105.2 vs 100).
Scale: 10th–90th percentile of metro/non-metro areas with a BEA price parity
BEA Regional Price Parity (all items)
RPP 105.2
+5.2% vs U.S. average · BEA 2024 · Boulder, CO metro
HUD Fair Market Rent, 2-BR
$2,124/mo
FY2026 · Boulder, CO MSA
State income tax (top marginal rate)
4.40%
flat · TY2025
Family-of-four monthly budget total
$10,215/mo
3BR rent + food + childcare + taxes + transport · federal sources
Single-adult monthly budget total
$4,974/mo
1BR rent + food + taxes + transport · federal sources
Local income tax
—
not applicable in Colorado · no modeled local income tax
Household budget figures are arithmetic floors using current federal sources at the grains documented in methodology. Not a recommended salary, not a poverty threshold, not a composite score.
10.1% foreign-born (U.S. median 14%); Spanish is the most-spoken language at home other than English (13.6% of residents 5+).
A quick read on Longmont's residents — nativity and languages spoken at home shown above, from the ACS 5-Year 2020–2024. The full demographic breakdown (age, race and ethnicity, household types, and educational attainment, each with its margin of error) lives on the demographics page.
Hottest month: July (90°F avg high). Coldest: January (16°F avg low). Annual precipitation: 15.7 in.
30-year climate normals (1991-2020) for Longmont from the U.S. National Oceanic and Atmospheric Administration. See methodology §15 for the gridded vs. station source path.
Average monthly highs & lows · 30-year normal (NOAA 1991–2020). Every number on this chart is an average.
bar = avg daily high → avg daily lowprecip in inches below each barprecip in millimeters below each bar
Composite risk spans 89.2–90.7/100 across 2 counties; most-cited top hazard is Lightning (in 1 of 2).
Natural-hazard exposure for Longmont from the U.S. Federal Emergency Management Agency's National Risk Index (FEMA NRI December 2025 v1.20.0). NRI is an expected-annual-loss composite calibrated on 1996–2019 historical losses, published at the U.S. county grain. See methodology §17.
Longmont spans 2 counties. We list each separately because hurricane, flood, and fire risk varies meaningfully across county lines — manufacturing a single “city-level” risk score would hide that signal.
County
NRI composite
Rating
Top hazards
Boulder County
90.7
Relatively Moderate
Lightning 99.0 Very High · Hail 98.4 Relatively High · Wildfire 97.9 Relatively High
Weld County
89.2
Relatively Moderate
Hail 99.0 Relatively High · Cold Wave 96.3 Relatively High · Tornado 95.1 Relatively High
Source: FEMA National Risk Index · FEMA NRI December 2025 v1.20.0 · methodology →
How fast is home internet in Longmont?
13 non-satellite ISPs serve the area; 99% of locations have gigabit-capable service per ISP filings.
Fixed broadband availability for Longmont from the U.S. Federal Communications Commission's Broadband Data Collection (BDC), as of June 30, 2025. Every speed and provider count below is an ISP-reported advertised maximum — not measured throughput. Actual delivered speeds typically run 60–80% of advertised. See methodology §16.
Measure
Value
Note
Providers serving this city
13 + satellite
distinct ISPs, excluding satellite-only
Fiber providers
12
offer fiber-to-the-premises somewhere in the BDC
Units with ≥100/20 Mbps fixed
100.0%
share of broadband-serviceable units, ISP-reported max
Locations with ≥100 Mbps upload
99.9%
derived: max(fiber ≥100/20, gigabit). Fiber is symmetric; gigabit is ≥100 up by definition
Units with ≥1 Gbps fixed
99.4%
share of broadband-serviceable units, ISP-reported max
Total broadband-serviceable units
46,810
residential locations in the FCC Fabric (not households)
Source: FCC BDC · as of June 30, 2025 · methodology →
In-state context.
Longmont sits at state rank #13 among 272 cities in Colorado. Nearby in the state ranking:
Just above in the profiled set: Deltona, FL · #342 · 100,267 residents.
Just below in the profiled set: Federal Way, WA · #344 · 99,729 residents.
Quick travel facts for Longmont
Quick travel facts.
Nearest commercial airport
Rocky Mountain Metropolitan Airport(BJC) · 18 mi 29 km from city centroid
Best months to visit
Sep, Oct · months when the avg high sits in 65–80°F and precipitation is at or below the city's median monthly precip
Sources: elevation from USGS Elevation Point Query Service (3DEP) · nearest airport from OurAirports CSV (FAA-aligned, type=large/medium, scheduled_service=yes) · best months derived from NOAA 1991-2020 normals · methodology →
Frequently asked questions about Longmont.
How many people live in Longmont, CO?
Longmont has 100,109 residents as of July 1, 2025, making it the #343 largest city in the United States and #13 in Colorado. Source: U.S. Census Bureau Population Estimates Program, Vintage 2025.
Is Longmont growing or shrinking?
Longmont has grown 1.2% since the April 2020 census baseline, adding 1,209 residents, including a 0.5% increase from 2024 to 2025. Source: Census PEP Vintage 2025.
What was Longmont's population in the 2020 census?
The GEOID for Longmont is 0845970. These are the official datasets used by this profile's main data modules; click "methodology" for inclusion rules and the V2019 ↔ V2025 seam, or "source" for the raw publisher page. The headline population value above includes a source-detail disclosure with publisher, dataset, vintage, native geography, transformation, and caveat.
