Custer County, Idaho Population 2026
Updated April 2026 · US Census ACS 2023 5-Year Estimates · 40th-largest in Idaho
The population of Custer County, Idaho is 4,411 as of the 2023 American Community Survey, making it the 40th-largest county in Idaho. The median household income is $56,957, the median home value is $295,600, and the median age is 59.5.
The population of Custer County has grown 5.5% since 2010 (4,357 → 4,597), a +0.38% annualized rate.
4,411
Population
+0.38%
Annual growth
1
People / sq mi
$56,957
Median Income
$295,600
Median Home Value
Custer County covers 4,922 sq mi of land at 0.9 people per square mile.
About Custer County, ID
Custer County is a county in Idaho with a population of 4,411. It ranks #40 among counties in Idaho by population. The median age is 59.5, older than the national median. The population is 52.1% male and 47.9% female.
The median household income in Custer County is $56,957, below the US median of $74,580. 4.9% of residents live below the federal poverty level. Home values sit at a median of $295,600, with monthly rent averaging $744. The homeownership rate of 77.7% is higher than the national rate of 64.8%.
Educational attainment in Custer County reflects 25.2% of adults 25 and older holding a bachelor's degree or higher, below the national average of 34.3%. Roughly 25.0% of workers primarily work from home, noticeably above the national work-from-home rate of 14.2%. The average commute is 16.8 minutes each way.
Custer County Population History (2010-2024)
The county of Custer County had a population of 4,357 in 2010 and 4,597 in 2024, a 5.5% growth over 14 years. The peak was 4,597 in 2024. Average annual growth rate: 0.40%.
4,597
Population (2024)
4,357
Population (2010)
4,597
Peak (2024)
0.40%
Avg Annual Growth
| Year | Population |
|---|---|
| 2010 | 4,357 |
| 2011 | 4,325 |
| 2012 | 4,327 |
| 2013 | 4,226 |
| 2014 | 4,134 |
| 2015 | 4,061 |
| 2016 | 4,089 |
| 2017 | 4,138 |
| 2018 | 4,216 |
| 2019 | 4,273 |
| 2020 | 4,269 |
| 2021 | 4,444 |
| 2022 | 4,503 |
| 2023 | 4,531 |
| 2024 | 4,597 |
Race & Ethnicity
| White | 89.9% |
| Black or African American | 0.3% |
| Asian | 0.0% |
| Hispanic or Latino (any race) | 3.4% |
| Two or More Races | 0.0% |
Age & Sex
59.5
Median Age
47.9%
Female
52.1%
Male
36.2%
Age 65+
Age Distribution
Children (under 15): 9.2% · Seniors (65+): 36.2%
Income & Poverty
| Median household income | $56,957$-17,679 vs state |
| Mean household income | $65,974 |
| Per-capita income | $29,993 |
| Poverty rate | 4.9%-2.1% vs state |
| Unemployment rate | 1.0% |
| Employment-to-population | 46.9% |
Top Industries by Employment
The largest employment sector in Custer County is professional & business services, accounting for 22.4% of workers.
How residents commute
0.9%
Drive alone
4.2%
Carpool
56.6%
Public transit
25.0%
Work from home
16.8 min
Avg commute
Housing
$295,600$-80,400 vs state
Median home value
$744
Median rent
77.7%
Homeownership rate
3,164
Total housing units
61.1%
Occupied
38.9%
Vacant
22.3%
Renter-occupied
Social & access
85.9%
With health insurance
90.5%
With broadband internet
54.7%
Foreign-born
13.5%
Veterans (18+)
27.1%
With a disability
98.2%
Speak language other than English at home
Education
93.6%
High School+
25.2%
Bachelor's+
Largest cities in Idaho
Other counties in Idaho
Part of Idaho
Metro areas in Idaho
County rankings
Frequently Asked Questions
Custer County, Idaho has a population of 4,411 according to the US Census Bureau's 2023 American Community Survey 5-year estimates, making it the 40th-largest county in Idaho. Population density is 1 people per square mile.
The population of Custer County has grown 5.5% since 2010 (4,357 → 4,597), a +0.38% annualized rate.
The median household income in Custer County, Idaho is $56,957, with mean (average) household income of $65,974 and per-capita income of $29,993. 4.9% of residents live below the federal poverty level.
In Custer County, the largest racial and ethnic groups are White (89.9%), Hispanic or Latino (3.4%), Black or African American (0.3%). Figures are from the US Census Bureau's 2023 ACS 5-year estimates and reflect self-reported responses.
The median age in Custer County, Idaho is 59.5 years. Residents are 47.9% female and 52.1% male.
The median home value in Custer County is $295,600 and median monthly rent is $744. 77.7% of occupied housing units are owner-occupied. The county has 3,164 total housing units, 38.9% of which are vacant.
The largest employment sector in Custer County, Idaho is professional, scientific, and management services, employing 22.4% of workers. The unemployment rate is 1.0%.
Boise City is among the largest cities associated with Custer County, Idaho, with a population of 235,701.
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Statewide data for Idaho
Population, race, income, age, and trends across Idaho
Data from the American Community Survey (ACS) 5-Year estimates.
Source: U.S. Census Bureau ACS, 2026.