Gallatin County, Montana Population 2026
Updated April 2026 · US Census ACS 2023 5-Year Estimates · 2nd-largest in Montana
The population of Gallatin County, Montana is 122,194 as of the 2023 American Community Survey, making it the 2nd-largest county in Montana. The median household income is $87,454, the median home value is $604,900, and the median age is 33.8.
The population of Gallatin County has grown 41.6% since 2010 (89,662 → 126,984), a +2.52% annualized rate.
122,194
Population
+2.52%
Annual growth
47
People / sq mi
$87,454
Median Income
$604,900
Median Home Value
Gallatin County covers 2,605 sq mi of land at 46.9 people per square mile.
About Gallatin County, MT
Gallatin County is a county in Montana with a population of 122,194. It ranks #2 among counties in Montana by population. The median age is 33.8, younger than the national median. The population is 52.3% male and 47.7% female.
The median household income in Gallatin County is $87,454, above the US median of $74,580. 4.1% of residents live below the federal poverty level. Home values sit at a median of $604,900, with monthly rent averaging $1,574. The homeownership rate of 61.5% is lower than the national rate of 64.8%.
Educational attainment in Gallatin County reflects 53.1% of adults 25 and older holding a bachelor's degree or higher, above the national average of 34.3%. Roughly 14.9% of workers primarily work from home, similar to the national work-from-home rate of 14.2%. The average commute is 18.8 minutes each way.
Gallatin County Population History (2010-2024)
The county of Gallatin County had a population of 89,662 in 2010 and 126,984 in 2024, a 41.6% growth over 14 years. The peak was 126,984 in 2024. Average annual growth rate: 2.52%.
126,984
Population (2024)
89,662
Population (2010)
126,984
Peak (2024)
2.52%
Avg Annual Growth
| Year | Population |
|---|---|
| 2010 | 89,662 |
| 2011 | 91,413 |
| 2012 | 92,627 |
| 2013 | 94,885 |
| 2014 | 97,629 |
| 2015 | 101,043 |
| 2016 | 104,999 |
| 2017 | 108,850 |
| 2018 | 111,878 |
| 2019 | 114,472 |
| 2020 | 119,607 |
| 2021 | 123,119 |
| 2022 | 124,733 |
| 2023 | 125,929 |
| 2024 | 126,984 |
Race & Ethnicity
| White | 89.7% |
| Black or African American | 0.5% |
| Asian | 0.1% |
| Hispanic or Latino (any race) | 2.0% |
| Two or More Races | 0.0% |
Age & Sex
33.8
Median Age
47.7%
Female
52.3%
Male
13.3%
Age 65+
Age Distribution
Children (under 15): 15.9% · Seniors (65+): 13.3%
Income & Poverty
| Median household income | $87,454+$17,532 vs state |
| Mean household income | $124,551 |
| Per-capita income | $51,148 |
| Poverty rate | 4.1%-3.0% vs state |
| Unemployment rate | 1.7% |
| Employment-to-population | 69.3% |
Top Industries by Employment
The largest employment sector in Gallatin County is professional & business services, accounting for 21.9% of workers.
How residents commute
0.5%
Drive alone
5.4%
Carpool
68.1%
Public transit
14.9%
Work from home
18.8 min
Avg commute
Housing
$604,900+$266,800 vs state
Median home value
$1,574
Median rent
61.5%
Homeownership rate
55,589
Total housing units
90.0%
Occupied
10.0%
Vacant
38.5%
Renter-occupied
Social & access
92.7%
With health insurance
97.3%
With broadband internet
57.8%
Foreign-born
5.4%
Veterans (18+)
8.8%
With a disability
94.7%
Speak language other than English at home
Education
97.2%
High School+
53.1%
Bachelor's+
Largest cities in Montana
Other counties in Montana
Part of Montana
Metro areas in Montana
County rankings
Frequently Asked Questions
Gallatin County, Montana has a population of 122,194 according to the US Census Bureau's 2023 American Community Survey 5-year estimates, making it the 2nd-largest county in Montana. Population density is 47 people per square mile.
The population of Gallatin County has grown 41.6% since 2010 (89,662 → 126,984), a +2.52% annualized rate.
The median household income in Gallatin County, Montana is $87,454, with mean (average) household income of $124,551 and per-capita income of $51,148. 4.1% of residents live below the federal poverty level.
In Gallatin County, the largest racial and ethnic groups are White (89.7%), Hispanic or Latino (2.0%), Black or African American (0.5%). Figures are from the US Census Bureau's 2023 ACS 5-year estimates and reflect self-reported responses.
The median age in Gallatin County, Montana is 33.8 years. Residents are 47.7% female and 52.3% male.
The median home value in Gallatin County is $604,900 and median monthly rent is $1,574. 61.5% of occupied housing units are owner-occupied. The county has 55,589 total housing units, 10.0% of which are vacant.
The largest employment sector in Gallatin County, Montana is professional, scientific, and management services, employing 21.9% of workers. The unemployment rate is 1.7%.
Billings is among the largest cities associated with Gallatin County, Montana, with a population of 118,321.
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Statewide data for Montana
Population, race, income, age, and trends across Montana
Data from the American Community Survey (ACS) 5-Year estimates.
Source: U.S. Census Bureau ACS, 2026.