Data / Rankings / Population density / Counties in Montana

Counties in Montana by population density, 2025

Yellowstone County had the highest population density of 56 counties in 2025, at 25.3 inhabitants per km². Garfield County had the lowest, at 0.1 inhabitants per km². The median was 1.1 inhabitants per km² and the figure for Montana was 3 inhabitants per km². Source: the U.S. Census Bureau.

Highest25.3Yellowstone County
Lowest0.1Garfield County
Median1.156 counties
Montana3History

All counties, 2025

CSVChart (SVG)

Yellowstone CountyYellowstone County: 25.3 inhabitants per km²25.3Silver Bow CountySilver Bow County: 19.4 inhabitants per km²19.4Gallatin CountyGallatin County: 19.1 inhabitants per km²19.1Missoula CountyMissoula County: 18.4 inhabitants per km²18.4Cascade CountyCascade County: 12.2 inhabitants per km²12.2Flathead CountyFlathead County: 8.8 inhabitants per km²8.8Lake CountyLake County: 8.7 inhabitants per km²8.7Lewis and Clark CountyLewis and Clark County: 8.4 inhabitants per km²8.4Ravalli CountyRavalli County: 7.8 inhabitants per km²7.8Deer Lodge CountyDeer Lodge County: 5.1 inhabitants per km²5.1Jefferson CountyJefferson County: 3.1 inhabitants per km²3.1Broadwater CountyBroadwater County: 2.8 inhabitants per km²2.8Park CountyPark County: 2.5 inhabitants per km²2.5Lincoln CountyLincoln County: 2.4 inhabitants per km²2.4Carbon CountyCarbon County: 2.2 inhabitants per km²2.2Hill CountyHill County: 2.2 inhabitants per km²2.2Richland CountyRichland County: 2.1 inhabitants per km²2.1Stillwater CountyStillwater County: 2 inhabitants per km²2Sanders CountySanders County: 2 inhabitants per km²2Glacier CountyGlacier County: 1.7 inhabitants per km²1.7Roosevelt CountyRoosevelt County: 1.7 inhabitants per km²1.7Mineral CountyMineral County: 1.6 inhabitants per km²1.6Pondera CountyPondera County: 1.4 inhabitants per km²1.4Dawson CountyDawson County: 1.4 inhabitants per km²1.4Custer CountyCuster County: 1.2 inhabitants per km²1.2Powell CountyPowell County: 1.2 inhabitants per km²1.2Musselshell CountyMusselshell County: 1.2 inhabitants per km²1.2Teton CountyTeton County: 1.1 inhabitants per km²1.1Madison CountyMadison County: 1.1 inhabitants per km²1.1Fergus CountyFergus County: 1.1 inhabitants per km²1.1Toole CountyToole County: 1.1 inhabitants per km²1.1Big Horn CountyBig Horn County: 1 inhabitants per km²1Granite CountyGranite County: 0.8 inhabitants per km²0.8Sheridan CountySheridan County: 0.8 inhabitants per km²0.8Sweet Grass CountySweet Grass County: 0.8 inhabitants per km²0.8Fallon CountyFallon County: 0.7 inhabitants per km²0.7Beaverhead CountyBeaverhead County: 0.7 inhabitants per km²0.7Rosebud CountyRosebud County: 0.6 inhabitants per km²0.6Blaine CountyBlaine County: 0.6 inhabitants per km²0.6Valley CountyValley County: 0.6 inhabitants per km²0.6Chouteau CountyChouteau County: 0.6 inhabitants per km²0.6Wheatland CountyWheatland County: 0.6 inhabitants per km²0.6Liberty CountyLiberty County: 0.5 inhabitants per km²0.5Judith Basin CountyJudith Basin County: 0.4 inhabitants per km²0.4Daniels CountyDaniels County: 0.4 inhabitants per km²0.4Wibaux CountyWibaux County: 0.4 inhabitants per km²0.4Meagher CountyMeagher County: 0.3 inhabitants per km²0.3Phillips CountyPhillips County: 0.3 inhabitants per km²0.3Treasure CountyTreasure County: 0.3 inhabitants per km²0.3Golden Valley CountyGolden Valley County: 0.3 inhabitants per km²0.3McCone CountyMcCone County: 0.3 inhabitants per km²0.3Prairie CountyPrairie County: 0.2 inhabitants per km²0.2Powder River CountyPowder River County: 0.2 inhabitants per km²0.2Carter CountyCarter County: 0.2 inhabitants per km²0.2Petroleum CountyPetroleum County: 0.1 inhabitants per km²0.1Garfield CountyGarfield County: 0.1 inhabitants per km²0.1
inhabitants per km². Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-09.

Full ranking

RankCounties2025
inhabitants per km²		Change on 2024
1Yellowstone County25.3+0.7%
2Silver Bow County19.4+0.1%
3Gallatin County19.1+1%
4Missoula County18.4+0.8%
5Cascade County12.2+0.4%
6Flathead County8.8+0.9%
7Lake County8.70%
8Lewis and Clark County8.4+0.3%
9Ravalli County7.8+1.1%
10Deer Lodge County5.1-0.6%
11Jefferson County3.1+0.7%
12Broadwater County2.8+2.5%
13Park County2.5+0.2%
14Lincoln County2.4+0.8%
15Carbon County2.2-0.3%
16Hill County2.2+0.3%
17Richland County2.1+2.7%
18Stillwater County2+0.2%
19Sanders County2+1.2%
20Glacier County1.7-0.3%
21Roosevelt County1.7+0.3%
22Mineral County1.6-0.1%
23Pondera County1.4+0.1%
24Dawson County1.4-0.6%
25Custer County1.2+0.5%
26Powell County1.2+0.5%
27Musselshell County1.2+2.4%
28Teton County1.1+0.9%
29Madison County1.1+2.6%
30Fergus County1.10%
31Toole County1.1+1.2%
32Big Horn County1-0.7%
33Granite County0.8+0.6%
34Sheridan County0.8-1.2%
35Sweet Grass County0.8-1.4%
36Fallon County0.70%
37Beaverhead County0.7+0.6%
38Rosebud County0.6+0.3%
39Blaine County0.6-0.2%
40Valley County0.60%
41Chouteau County0.6+0.2%
41Wheatland County0.6+2%
43Liberty County0.5+0.2%
44Judith Basin County0.4+2.1%
45Daniels County0.4-2%
46Wibaux County0.4-3%
47Meagher County0.3+2.1%
48Phillips County0.3+0.3%
49Treasure County0.3-1%
50Golden Valley County0.30%
51McCone County0.30%
52Prairie County0.2+0.4%
53Powder River County0.2+1%
54Carter County0.2-2.4%
55Petroleum County0.1+2.4%
56Garfield County0.1-2.1%

Other periods

About this ranking

Resident population divided by land area in km². World Bank figures use mid-year population and land area excluding inland water.

United States: Census Bureau population estimates for 1 July divided by land area (water excluded) from the latest Census Gazetteer files. US tables often give people per square mile; multiply persons per km² by 2.59 to compare.

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 resident population on 1 July divided by land area from the latest Census Gazetteer files, persons per km². https://www2.census.gov/programs-surveys/popest/datasets/2020-2025/. Retrieved 2026-10-09.

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Questions

Which county has the highest population density?

Yellowstone County, with 25.3 inhabitants per km² in 2025, according to the U.S. Census Bureau.

Which county has the lowest population density?

Garfield County, with 0.1 inhabitants per km² in 2025.

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 resident population on 1 July divided by land area from the latest Census Gazetteer files, persons per km². Retrieved 2026-10-09.

Population density: other rankings

Counties in Montana: more rankings