List of Montana Counties by Population and Size (+Map)

Montana is undoubtedly one of the most underrated states in the country. From towering, snowcapped mountains to placid and glass-like lakes (and most importantly, wide open plains and prairies) – Montana has it all.

Like all other states, Montana is divided up into counties, with 56 individual counties making up the entirety of the state.

Each county is unique and varies in size and population, and you will find that locals are very proud of their area!

This guide covers each county in Montana and provides you with all the information you need at a glance, including:

Country formed
Population
Area size

And more. Let’s get into it!

Jump to: Counties in Montana By Population and Size

Counties in Montana

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

B

C

D

F

G

H

Hill County

J

L

M

P

R

S

T

V

Valley County

W

Y

Yellowstone County

The Counties in Montana By When It Was Formed, Size and Population

Here is a breakdown of each county and all the essential information you need to know!

Data source: 2022 census conducted by the U.S. Census Bureau

County	Formed	Area	Population (2022)	Population (2021)	Change
Beaverhead	1865	5,572 sq mi	9,719	9532	+187
Big Horn	1913	5,015 sq mi	12,851	12932	-81
Blaine	1912	4,239 sq mi	6,936	6982	-46
Broadwater	1897	1,239 sq mi	7,793	7323	+470
Carbon	1895	2,062 sq mi	11,179	10862	+317
Carter	1917	3,348 sq mi	1,382	1410	-28
Cascade	1887	2,711 sq mi	84,864	84498	+366
Chouteau	1865	3,997 sq mi	5,898	5916	-18
Custer	1865	3,793 sq mi	12,032	11971	+61
Daniels	1920	1,426 sq mi	1,628	1669	-41
Dawson	1870	2,383 sq mi	8,830	8866	-36
Deer Lodge	1865	741 sq mi	9510	9506	+4
Fallon	1913	1,623 sq mi	3,011	2984	+27
Fergus	1885	4,350 sq mi	11,663	11609	+54
Flathead	1893	5256 sq mi	111,814	108725	+3,089
Gallatin	1865	2632 sq mi	124,857	123051	+1,806
Garfield	1919	4,847 sq mi	12,18	1210	+8
Glacier	1919	3,037 sq mi	13,681	13743	-62
Golden Valley	1920	1,176 sq mi`	835	818	+17
Granite	1893	1,733 sq mi	3,502	3355	+147
Hill	1912	2,916 sq mi	16,068	16175	-107
Jefferson	1865	1,659 sq m	12,826	12472	+354
Judith Basin	1920	1,871 sq mi	2,105	2052	+53
Lake	1923	1,654 sq mi	32,853	32075	+778
Lewis and Clark	1865	3,498 sq mi	73,832	73830.671	+1.329
Liberty	1920	1,447 sq mi	1,972	2010	-38
Lincoln	1909	3,675 sq m	21,525	20571	+954
Madison	1865	3,603 sq m	9,265	8944	+321
McCone	1919	2,683 sq mi	1,709	1711	-2
Meagher	1867	2,395 sq mi	2,013	1960	+53
Mineral	1914	1,223 sq mi	5,058	4868	+190
Missoula	1864	2618 sq mi	121,041	119806	+1,235
Musselshell	1911	1,871 sq mi	5,197	4912	+285
Park	1887	2,813 sq mi	17,790	17531	+259
Petroleum	1925	1,674 sq mi	524	522	+2
Phillips	1915	5,212 sq mi	4,240	4216	+24
Pondera	1919	1,640 sq m	6,078	6018	+60
Powder River	1919	3,298 sq mi	1,725	1707	+18
Powell	1901	2,333 sq mi	7,051	7012	+39
Prarie	1915	1,743 sq mi	1,107	1101	+6
Ravalli	1893	2,400 sq mi	47,298	46125	+1,173
Richland	1914	2,103 sq mi	11,237	11342	-105
Roosevelt	1919	2,369 sq mi	10,572	10808	-236
Rosebud	1901	5,027 sq mi	8,088	8077	+11
Sanders	1905	2,790 sq mi	9,719	9532	+187
Sheridan	1913	1,677 sq mi	3,564	3569	-5
Silver Bow	1881	719 sq mi	36,068	35554	+514
Stillwater	1913	1,805 sq mi	9,177	9026	+151
Sweet Grass	1895	1,862 sq mi	3,715	3705	+10
Teton	1893	2,293 sq mi	6,368	6282	+86
Toole	1914	1,946 sq mi	5,082	5010	+72
Treasure	1919	984 sq mi	758	769	-11
Valley	1893	5,062 sq mi	7,513	7556	-43
Wheatland	1917	1,428 sq mi	2,032	2045	-13
Wibaux	1914	890 sq mi	919	935	-16
Yellowstone	1883	2633 sq mi	169,852	167397	+2,455