Stillwater County, Montana Population 2026
Updated April 2026 · US Census ACS 2023 5-Year Estimates · 24th-largest in Montana
The population of Stillwater County, Montana is 9,052 as of the 2023 American Community Survey, making it the 24th-largest county in Montana. The median household income is $81,503, the median home value is $355,600, and the median age is 47.4.
The population of Stillwater County has grown 3.7% since 2010 (9,112 → 9,450), a +0.26% annualized rate.
9,052
Population
+0.26%
Annual growth
5
People / sq mi
$81,503
Median Income
$355,600
Median Home Value
Stillwater County covers 1,797 sq mi of land at 5.0 people per square mile.
About Stillwater County, MT
Stillwater County is a county in Montana with a population of 9,052. It ranks #24 among counties in Montana by population. The median age is 47.4, older than the national median. The population is 50.2% male and 49.8% female.
The median household income in Stillwater County is $81,503, above the US median of $74,580. 6.0% of residents live below the federal poverty level. Home values sit at a median of $355,600, with monthly rent averaging $968. The homeownership rate of 80.8% is higher than the national rate of 64.8%.
Educational attainment in Stillwater County reflects 29.8% of adults 25 and older holding a bachelor's degree or higher, below the national average of 34.3%. Roughly 7.9% of workers primarily work from home, below the national work-from-home rate of 14.2%. The average commute is 28.5 minutes each way.
Stillwater County Population History (2010-2024)
The county of Stillwater County had a population of 9,112 in 2010 and 9,450 in 2024, a 3.7% growth over 14 years. The peak was 9,671 in 2019. Average annual growth rate: 0.29%.
9,450
Population (2024)
9,112
Population (2010)
9,671
Peak (2019)
0.29%
Avg Annual Growth
| Year | Population |
|---|---|
| 2010 | 9,112 |
| 2011 | 9,153 |
| 2012 | 9,161 |
| 2013 | 9,250 |
| 2014 | 9,230 |
| 2015 | 9,419 |
| 2016 | 9,349 |
| 2017 | 9,408 |
| 2018 | 9,496 |
| 2019 | 9,671 |
| 2020 | 9,002 |
| 2021 | 9,026 |
| 2022 | 9,194 |
| 2023 | 9,237 |
| 2024 | 9,450 |
Race & Ethnicity
| White | 93.3% |
| Black or African American | 0.1% |
| Asian | 0.0% |
| Hispanic or Latino (any race) | 3.2% |
| Two or More Races | 0.0% |
Age & Sex
47.4
Median Age
49.8%
Female
50.2%
Male
25.0%
Age 65+
Age Distribution
Children (under 15): 16.3% · Seniors (65+): 25.0%
Income & Poverty
| Median household income | $81,503+$11,581 vs state |
| Mean household income | $111,489 |
| Per-capita income | $48,923 |
| Poverty rate | 6.0%-1.1% vs state |
| Unemployment rate | 2.1% |
| Employment-to-population | 59.6% |
Top Industries by Employment
The largest employment sector in Stillwater County is agriculture, accounting for 20.5% of workers.
How residents commute
3.3%
Drive alone
4.1%
Carpool
61.9%
Public transit
7.9%
Work from home
28.5 min
Avg commute
Housing
$355,600+$17,500 vs state
Median home value
$968
Median rent
80.8%
Homeownership rate
4,657
Total housing units
83.1%
Occupied
16.9%
Vacant
19.2%
Renter-occupied
Social & access
95.4%
With health insurance
92.9%
With broadband internet
46.7%
Foreign-born
11.6%
Veterans (18+)
17.2%
With a disability
98.8%
Speak language other than English at home
Education
93.1%
High School+
29.8%
Bachelor's+
Largest cities in Montana
Other counties in Montana
Part of Montana
Metro areas in Montana
County rankings
Frequently Asked Questions
Stillwater County, Montana has a population of 9,052 according to the US Census Bureau's 2023 American Community Survey 5-year estimates, making it the 24th-largest county in Montana. Population density is 5 people per square mile.
The population of Stillwater County has grown 3.7% since 2010 (9,112 → 9,450), a +0.26% annualized rate.
The median household income in Stillwater County, Montana is $81,503, with mean (average) household income of $111,489 and per-capita income of $48,923. 6.0% of residents live below the federal poverty level.
In Stillwater County, the largest racial and ethnic groups are White (93.3%), Hispanic or Latino (3.2%), Black or African American (0.1%). Figures are from the US Census Bureau's 2023 ACS 5-year estimates and reflect self-reported responses.
The median age in Stillwater County, Montana is 47.4 years. Residents are 49.8% female and 50.2% male.
The median home value in Stillwater County is $355,600 and median monthly rent is $968. 80.8% of occupied housing units are owner-occupied. The county has 4,657 total housing units, 16.9% of which are vacant.
The largest employment sector in Stillwater County, Montana is agriculture, forestry, fishing, and mining, employing 20.5% of workers. The unemployment rate is 2.1%.
Billings is among the largest cities associated with Stillwater 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.