Data / Rankings / Population aged 18 to 64 / Counties in Montana

Counties in Montana by population aged 18 to 64

Gallatin County had the highest population aged 18 to 64 of 56 counties in 2022, at 67.2%. Prairie County had the lowest, at 45%. The median was 53.5% and the figure for Montana was 58.2%. Source: the U.S. Census Bureau.

Keep it in a collection in your library.
Highest67.2Gallatin County
Lowest45Prairie County
Median53.556 counties
Montana58.2History

Map of counties, 2022

Beaverhead County: 56.8 %Big Horn County: 54.5 %Blaine County: 55.1 %Broadwater County: 55.9 %Carbon County: 54.5 %Carter County: 50.3 %Cascade County: 58 %Chouteau County: 53.8 %Custer County: 57.3 %Daniels County: 51.2 %Dawson County: 56.9 %Deer Lodge County: 57.8 %Fallon County: 54 %Fergus County: 52.2 %Flathead County: 56.2 %Gallatin County: 67.2 %Garfield County: 49.5 %Glacier County: 56.3 %Golden Valley County: 50.4 %Granite County: 54.6 %Hill County: 55.4 %Jefferson County: 54.3 %Judith Basin County: 52.1 %Lake County: 52.6 %Lewis and Clark County: 58.3 %Liberty County: 51.3 %Lincoln County: 51.1 %McCone County: 53.2 %Madison County: 54 %Meagher County: 53.8 %Mineral County: 53.3 %Missoula County: 63 %Musselshell County: 52.4 %Park County: 59.4 %Petroleum County: 52 %Phillips County: 51.8 %Pondera County: 52.7 %Powder River County: 51.2 %Powell County: 62 %Prairie County: 45 %Ravalli County: 52.6 %Richland County: 58.8 %Roosevelt County: 53.5 %Rosebud County: 53.6 %Sanders County: 50.2 %Sheridan County: 52.2 %Silver Bow County: 59.2 %Stillwater County: 53 %Sweet Grass County: 52.1 %Teton County: 52.2 %Toole County: 61.3 %Treasure County: 50.5 %Valley County: 53.3 %Wheatland County: 51 %Wibaux County: 53.4 %Yellowstone County: 58.7 %
  • Under 51
  • 51 to 52
  • 52 to 54
  • 54 to 55
  • 55 to 58
  • 58 and over
%, 2022. Source: Invokely calculation with data from U.S. Census Bureau. Boundaries: U.S. Census Bureau cartographic boundary files.

All counties, 2022

Gallatin County: 67.2 %Gallatin County67.2Missoula County: 63 %Missoula County63Powell County: 62 %Powell County62Toole County: 61.3 %Toole County61.3Park County: 59.4 %Park County59.4Silver Bow County: 59.2 %Silver Bow County59.2Richland County: 58.8 %Richland County58.8Yellowstone County: 58.7 %Yellowstone County58.7Lewis and Clark County: 58.3 %Lewis and Clark County58.3Cascade County: 58 %Cascade County58Deer Lodge County: 57.8 %Deer Lodge County57.8Custer County: 57.3 %Custer County57.3Dawson County: 56.9 %Dawson County56.9Beaverhead County: 56.8 %Beaverhead County56.8Glacier County: 56.3 %Glacier County56.3Flathead County: 56.2 %Flathead County56.2Broadwater County: 55.9 %Broadwater County55.9Hill County: 55.4 %Hill County55.4Blaine County: 55.1 %Blaine County55.1Granite County: 54.6 %Granite County54.6Big Horn County: 54.5 %Big Horn County54.5Carbon County: 54.5 %Carbon County54.5Jefferson County: 54.3 %Jefferson County54.3Fallon County: 54 %Fallon County54Madison County: 54 %Madison County54Chouteau County: 53.8 %Chouteau County53.8Meagher County: 53.8 %Meagher County53.8Rosebud County: 53.6 %Rosebud County53.6Roosevelt County: 53.5 %Roosevelt County53.5Wibaux County: 53.4 %Wibaux County53.4Valley County: 53.3 %Valley County53.3Mineral County: 53.3 %Mineral County53.3McCone County: 53.2 %McCone County53.2Stillwater County: 53 %Stillwater County53Pondera County: 52.7 %Pondera County52.7Ravalli County: 52.6 %Ravalli County52.6Lake County: 52.6 %Lake County52.6Musselshell County: 52.4 %Musselshell County52.4Teton County: 52.2 %Teton County52.2Sheridan County: 52.2 %Sheridan County52.2Fergus County: 52.2 %Fergus County52.2Sweet Grass County: 52.1 %Sweet Grass County52.1Judith Basin County: 52.1 %Judith Basin County52.1Petroleum County: 52 %Petroleum County52Phillips County: 51.8 %Phillips County51.8Liberty County: 51.3 %Liberty County51.3Daniels County: 51.2 %Daniels County51.2Powder River County: 51.2 %Powder River County51.2Lincoln County: 51.1 %Lincoln County51.1Wheatland County: 51 %Wheatland County51Treasure County: 50.5 %Treasure County50.5Golden Valley County: 50.4 %Golden Valley County50.4Carter County: 50.3 %Carter County50.3Sanders County: 50.2 %Sanders County50.2Garfield County: 49.5 %Garfield County49.5Prairie County: 45 %Prairie County45Gallatin County: 67.2 %Gallatin County67.2Missoula County: 63 %Missoula County63Powell County: 62 %Powell County62Toole County: 61.3 %Toole County61.3Park County: 59.4 %Park County59.4Silver Bow County: 59.2 %Silver Bow County59.2Richland County: 58.8 %Richland County58.8Yellowstone County: 58.7 %Yellowstone County58.7Lewis and Clark County: 58.3 %Lewis and Clark County58.3Cascade County: 58 %Cascade County58Deer Lodge County: 57.8 %Deer Lodge County57.8Custer County: 57.3 %Custer County57.3Dawson County: 56.9 %Dawson County56.9Beaverhead County: 56.8 %Beaverhead County56.8Glacier County: 56.3 %Glacier County56.3Flathead County: 56.2 %Flathead County56.2Broadwater County: 55.9 %Broadwater County55.9Hill County: 55.4 %Hill County55.4Blaine County: 55.1 %Blaine County55.1Granite County: 54.6 %Granite County54.6Big Horn County: 54.5 %Big Horn County54.5Carbon County: 54.5 %Carbon County54.5Jefferson County: 54.3 %Jefferson County54.3Fallon County: 54 %Fallon County54Madison County: 54 %Madison County54Chouteau County: 53.8 %Chouteau County53.8Meagher County: 53.8 %Meagher County53.8Rosebud County: 53.6 %Rosebud County53.6Roosevelt County: 53.5 %Roosevelt County53.5Wibaux County: 53.4 %Wibaux County53.4Valley County: 53.3 %Valley County53.3Mineral County: 53.3 %Mineral County53.3McCone County: 53.2 %McCone County53.2Stillwater County: 53 %Stillwater County53Pondera County: 52.7 %Pondera County52.7Ravalli County: 52.6 %Ravalli County52.6Lake County: 52.6 %Lake County52.6Musselshell County: 52.4 %Musselshell County52.4Teton County: 52.2 %Teton County52.2Sheridan County: 52.2 %Sheridan County52.2Fergus County: 52.2 %Fergus County52.2Sweet Grass County: 52.1 %Sweet Grass County52.1Judith Basin County: 52.1 %Judith Basin County52.1Petroleum County: 52 %Petroleum County52Phillips County: 51.8 %Phillips County51.8Liberty County: 51.3 %Liberty County51.3Daniels County: 51.2 %Daniels County51.2Powder River County: 51.2 %Powder River County51.2Lincoln County: 51.1 %Lincoln County51.1Wheatland County: 51 %Wheatland County51Treasure County: 50.5 %Treasure County50.5Golden Valley County: 50.4 %Golden Valley County50.4Carter County: 50.3 %Carter County50.3Sanders County: 50.2 %Sanders County50.2Garfield County: 49.5 %Garfield County49.5Prairie County: 45 %Prairie County45
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-12.

Full ranking

RankCounties2022 (%)Change on 2021
1Gallatin County67.2-0.1 pts
2Missoula County63-0.1 pts
3Powell County62-1.2 pts
4Toole County61.3+0.2 pts
5Park County59.4-0.2 pts
6Silver Bow County59.2+0.1 pts
7Richland County58.8-0.4 pts
8Yellowstone County58.7-0.2 pts
9Lewis and Clark County58.3-0.2 pts
10Cascade County58-0.2 pts
11Deer Lodge County57.8-0.5 pts
12Custer County57.30 pts
13Dawson County56.9-0.6 pts
14Beaverhead County56.8+0.3 pts
15Glacier County56.3+0.3 pts
16Flathead County56.2-0.1 pts
17Broadwater County55.9-0.4 pts
18Hill County55.4-0.8 pts
19Blaine County55.1+0.5 pts
20Granite County54.6+0.8 pts
21Big Horn County54.5+0.4 pts
22Carbon County54.5-0.7 pts
23Jefferson County54.3-0.6 pts
24Fallon County54-1.3 pts
25Madison County54+0.5 pts
26Chouteau County53.8-0.5 pts
27Meagher County53.8-0.2 pts
28Rosebud County53.6-0.6 pts
29Roosevelt County53.5-0 pts
30Wibaux County53.4+0.4 pts
31Valley County53.3-0.8 pts
32Mineral County53.3+0.1 pts
33McCone County53.2-0.4 pts
34Stillwater County53-0.8 pts
35Pondera County52.7-1 pts
36Ravalli County52.6-0.3 pts
37Lake County52.6-0 pts
38Musselshell County52.4-0.4 pts
39Teton County52.2-0.2 pts
40Sheridan County52.2-0.7 pts
41Fergus County52.2-0.4 pts
42Sweet Grass County52.1-0.4 pts
43Judith Basin County52.1+1.1 pts
44Petroleum County52-1.8 pts
45Phillips County51.8-0.5 pts
46Liberty County51.3-1.2 pts
47Daniels County51.2-1.1 pts
48Powder River County51.2-0.9 pts
49Lincoln County51.1+0.4 pts
50Wheatland County51-0.3 pts
51Treasure County50.5-0.5 pts
52Golden Valley County50.4-1.8 pts
53Carter County50.3-0.4 pts
54Sanders County50.2-0.1 pts
55Garfield County49.5+0.3 pts
56Prairie County45-1.5 pts

Other periods

About this ranking

Residents aged 18 to 64 as a percentage of total population on 1 July. United States: Census Bureau county population estimates by age; states and the nation are sums of their counties.

Not comparable with working-age shares for ages 15 to 64 used in EU and World Bank statistics.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. Equal values share a rank.

How to cite

U.S. Census Bureau. Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.

Citation styles

The publisher is the author. Invokely is named only as the place the figures were read, where a style asks for it.

APA 7

U.S. Census Bureau. (2026). Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties (Counties in Montana by population aged 18 to 64, 2022) [Data set]. Retrieved October 12, 2026, from https://www.census.gov/programs-surveys/popest/data/data-sets.html

MLA 9

Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties, Counties in Montana by population aged 18 to 64, 2022. U.S. Census Bureau, 25 June 2026, https://www.census.gov/programs-surveys/popest/data/data-sets.html. Invokely, https://invokely.ai/rankings/population-18-64/montana-counties?period=2022. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Census Bureau. 2026. Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. Counties in Montana by population aged 18 to 64, 2022. Dataset. Accessed October 12, 2026. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Also distributed by Invokely, https://invokely.ai/rankings/population-18-64/montana-counties?period=2022.

Harvard

U.S. Census Bureau (2026) Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties, Counties in Montana by population aged 18 to 64, 2022 [Dataset]. Available at: https://www.census.gov/programs-surveys/popest/data/data-sets.html, via Invokely: https://invokely.ai/rankings/population-18-64/montana-counties?period=2022 (Accessed: 12 October 2026).

BibTeX
@misc{census_counties_in_montana_by_2022,
  author = {{U.S. Census Bureau}},
  title = {{Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties: Counties in Montana by population aged 18 to 64, 2022}},
  year = {2026},
  howpublished = {Data set},
  url = {https://www.census.gov/programs-surveys/popest/data/data-sets.html},
  urldate = {2026-10-12},
  note = {Accessed via Invokely, https://invokely.ai/rankings/population-18-64/montana-counties?period=2022. Publisher attribution: U.S. Census Bureau. Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.},
}
RIS
TY  - DATA
AU  - U.S. Census Bureau
TI  - Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties: Counties in Montana by population aged 18 to 64, 2022
PY  - 2026
DA  - 2026/06/25
PB  - U.S. Census Bureau
DB  - Invokely
UR  - https://www.census.gov/programs-surveys/popest/data/data-sets.html
L2  - https://invokely.ai/rankings/population-18-64/montana-counties?period=2022
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/population-18-64/montana-counties?period=2022.
N1  - Publisher attribution: U.S. Census Bureau. Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.
ER  -
Embed this chart

Paste this code into a web page or a blog post. The chart shows the latest figures as they are published, with the source and a link back to this page.

Sites that read oEmbed links, such as WordPress, can show the chart when you paste the link to this page.

Use this data in your AI agent

Invokely serves this figure to AI assistants through MCP and to code through a REST API, with the source and citation attached. Ask your assistant:

Rank Counties in Montana by population aged 18 to 64 using official data, and cite the source.
rank_places {"indicator":"population_18_64_share","level":"province","within":"Montana","limit":10}
GET https://invokely.ai/api/v1/rank?indicator=population_18_64_share&level=province&within=Montana&limit=10

Connect Claude, ChatGPT or Cursor in one step. The trial answers 25 calls a day without an account.

Questions

Which county has the highest population aged 18 to 64?

Gallatin County, with 67.2% in 2022, according to the U.S. Census Bureau.

Which county has the lowest population aged 18 to 64?

Prairie County, with 45% in 2022.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Census Bureau, Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. Retrieved 2026-10-12.

Population aged 18 to 64: other rankings

Counties in Montana: more rankings