Custer County, Montana Population 2026
Updated April 2026 · US Census ACS 2023 5-Year Estimates · 17th-largest in Montana
The population of Custer County, Montana is 11,938 as of the 2023 American Community Survey, making it the 17th-largest county in Montana. The median household income is $63,585, the median home value is $204,200, and the median age is 42.6.
The population of Custer County has grown 2.3% since 2010 (11,691 → 11,964), a +0.17% annualized rate.
11,938
Population
+0.17%
Annual growth
3
People / sq mi
$63,585
Median Income
$204,200
Median Home Value
Custer County covers 3,783 sq mi of land at 3.2 people per square mile.
About Custer County, MT
Custer County stands apart on settlement density — it is among the most sparsely settled of US counties, at roughly 3 people per square mile. With 11,938 residents, Custer County is a county in Montana. It ranks #17 among counties in Montana by population.
Median household income is $63,585, below the US median of $78,538. The poverty rate, 5.6%, is on the lower side for US counties and below the national 12.4%. Median home value is $204,200, with typical rent around $918.
About 29.8% of adults 25 and older have a bachelor’s degree, below the 35.0% national figure. Most workers commute: only 5.8% work from home, below the national 14.0%, and the average commute runs about 14 minutes each way.
Custer County Population History (2010-2024)
The county of Custer County had a population of 11,691 in 2010 and 11,964 in 2024, a 2.3% growth over 14 years. The peak was 12,098 in 2015. Average annual growth rate: 0.18%.
11,964
Population (2024)
11,691
Population (2010)
12,098
Peak (2015)
0.18%
Avg Annual Growth
| Year | Population |
|---|---|
| 2010 | 11,691 |
| 2011 | 11,759 |
| 2012 | 11,804 |
| 2013 | 11,883 |
| 2014 | 12,023 |
| 2015 | 12,098 |
| 2016 | 11,844 |
| 2017 | 11,741 |
| 2018 | 11,576 |
| 2019 | 11,361 |
| 2020 | 11,863 |
| 2021 | 11,961 |
| 2022 | 12,005 |
| 2023 | 12,013 |
| 2024 | 11,964 |
Race & Ethnicity
| White | 91.2% |
| Black or African American | 0.4% |
| Asian | 0.0% |
| Hispanic or Latino (any race) | 4.0% |
| Two or More Races | 0.0% |
Age & Sex
42.6
Median Age
49.5%
Female
50.5%
Male
20.4%
Age 65+
Age Distribution
Children (under 15): 16.4% · Seniors (65+): 20.4%
Income & Poverty
| Median household income | $63,585$-6,337 vs state |
| Mean household income | $83,970 |
| Per-capita income | $35,864 |
| Poverty rate | 5.6%-1.5% vs state |
| Unemployment rate | 1.8% |
| Employment-to-population | 63.6% |
Top Industries by Employment
The largest employment sector in Custer County is professional & business services, accounting for 25.4% of workers.
How residents commute
0.1%
Drive alone
5.1%
Carpool
70.3%
Public transit
5.8%
Work from home
13.6 min
Avg commute
Housing
$204,200$-133,900 vs state
Median home value
$918
Median rent
68.5%
Homeownership rate
5,770
Total housing units
87.4%
Occupied
12.6%
Vacant
31.5%
Renter-occupied
Social & access
92.4%
With health insurance
93.8%
With broadband internet
34.2%
Foreign-born
9.1%
Veterans (18+)
20.2%
With a disability
96.9%
Speak language other than English at home
Education
94.7%
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
Custer County, Montana has a population of 11,938 according to the US Census Bureau's 2023 American Community Survey 5-year estimates, making it the 17th-largest county in Montana. Population density is 3 people per square mile.
The population of Custer County has grown 2.3% since 2010 (11,691 → 11,964), a +0.17% annualized rate.
The median household income in Custer County, Montana is $63,585, with mean (average) household income of $83,970 and per-capita income of $35,864. 5.6% of residents live below the federal poverty level.
In Custer County, the largest racial and ethnic groups are White (91.2%), Hispanic or Latino (4.0%), Black or African American (0.4%). Figures are from the US Census Bureau's 2023 ACS 5-year estimates and reflect self-reported responses.
The median age in Custer County, Montana is 42.6 years. Residents are 49.5% female and 50.5% male.
The median home value in Custer County is $204,200 and median monthly rent is $918. 68.5% of occupied housing units are owner-occupied. The county has 5,770 total housing units, 12.6% of which are vacant.
The largest employment sector in Custer County, Montana is professional, scientific, and management services, employing 25.4% of workers. The unemployment rate is 1.8%.
Billings is among the largest cities associated with Custer County, Montana, with a population of 118,321.
Custer County, MT Climate
Custer County, MT has an average annual temperature of 7.2°C (45°F) and receives about 346 mm of precipitation per year. The warmest month is July and the coldest is January. Figures are 1970–2000 climate normals.
7.2°C
Avg Temp
346
Precip (mm/yr)
Jul
Hottest Month
Jan
Coldest Month
| Month | Avg (°C/°F) | Precip |
|---|---|---|
| January | -9° / 16° | 12 mm |
| February | -5° / 24° | 8 mm |
| March | 1° / 34° | 14 mm |
| April | 7° / 45° | 37 mm |
| May | 13° / 55° | 59 mm |
| June | 18° / 65° | 67 mm |
| July | 22° / 72° | 36 mm |
| August | 22° / 71° | 29 mm |
| September | 15° / 59° | 34 mm |
| October | 8° / 46° | 24 mm |
| November | -1° / 31° | 14 mm |
| December | -7° / 20° | 12 mm |
1970–2000 normals from WorldClim 2.1 (~9 km grid). Precipitation can be less precise near mountains or coastlines, where rainfall varies sharply over short distances.
Best time to visit Custer County, MT
The most comfortable months to visit Custer County, MT are typically August, July and June, when temperatures are mildest and rainfall is relatively low. The hottest month is July (around 31°C high). The coldest is January (near -15°C low). June is usually the wettest month.
Where to stay near Custer County
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Data from the American Community Survey (ACS) 5-Year estimates.
Source: U.S. Census Bureau ACS, 2026.