Data / Population / Custer County

Population in Custer County

Population in Custer County was 12,034 in 2025, according to the U.S. Census Bureau. That is up 0.5% from 2024. That is the 17th highest of 56 counties in 2025.

2025, persons12,034
Change on 2024+0.5%
Rank17th of 56Counties in Montana ranked
Series high12,0342025
Series low11,8602020

Population in Custer County, 2020 to 2025

CSVChart (SVG)

11.9K11.9K12K12K12.1K2020202120222023202420252020: 11,860 persons2021: 11,960 persons2022: 11,997 persons2023: 12,003 persons2024: 11,977 persons2025: 12,034 persons
persons. Source: U.S. Census Bureau. Retrieved 2026-10-08, published 2026-03-26.
All 6 values
Periodpersons
202512,034
202411,977
202312,003
202211,997
202111,960
202011,860

Compared with Montana and United States

Place2025
Custer County12,034
Montana1,144,694
United States341,784,857

Rankings

Definition

Resident population. Spain and the EU: 1 January, with Spanish figures from the official municipal register (Padrón). United States: Census Bureau population estimates for 1 July. Other countries and the World: World Bank mid-year estimates, which count all residents regardless of legal status or citizenship.

For Denmark, Statistics Denmark counts the registered resident population on 1 January. Greenland and the Faroe Islands are excluded. The annual series selects the first-quarter reference date from FOLK1A. The World Bank series exists for every country, so use it (through compare) to rank countries on one basis.

How to cite

U.S. Census Bureau. Annual estimates of the resident population for the United States, states and counties, 1 July (Population Estimates Program). https://www2.census.gov/programs-surveys/popest/datasets/2020-2025/. Retrieved 2026-10-08.

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What is the latest population in Custer County? Cite the source.
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Questions

What is the population in Custer County?

Population in Custer County was 12,034 in 2025, according to the U.S. Census Bureau. That is up 0.5% from 2024. That is the 17th highest of 56 counties in 2025.

Where does this figure come from?

U.S. Census Bureau. Annual estimates of the resident population for the United States, states and counties, 1 July (Population Estimates Program). Retrieved by Invokely on 2026-10-08.

What was the highest population in Custer County?

12,034 in 2025, the highest value since 2020 in this series.

More statistics for Custer County

All statistics for Custer County