| Rank |
County |
Land Area |
| 1 |
Beaverhead County, Montana
|
5,541.6
|
| 2 |
Phillips County, Montana
|
5,140.0
|
| 3 |
Flathead County, Montana
|
5,087.7
|
| 4 |
Rosebud County, Montana
|
5,010.4
|
| 5 |
Big Horn County, Montana
|
4,995.5
|
| 6 |
Valley County, Montana
|
4,925.8
|
| 7 |
Garfield County, Montana
|
4,675.4
|
| 8 |
Fergus County, Montana
|
4,339.8
|
| 9 |
Blaine County, Montana
|
4,227.6
|
| 10 |
Chouteau County, Montana
|
3,972.5
|
| 11 |
Custer County, Montana
|
3,783.4
|
| 12 |
Lincoln County, Montana
|
3,612.9
|
| 13 |
Madison County, Montana
|
3,587.5
|
| 14 |
Lewis and Clark County, Montana
|
3,458.8
|
| 15 |
Carter County, Montana
|
3,340.8
|
| 16 |
Powder River County, Montana
|
3,297.3
|
| 17 |
Glacier County, Montana
|
2,995.9
|
| 18 |
Hill County, Montana
|
2,899.0
|
| 19 |
Park County, Montana
|
2,803.1
|
| 20 |
Sanders County, Montana
|
2,760.5
|
| 21 |
Cascade County, Montana
|
2,698.2
|
| 22 |
McCone County, Montana
|
2,643.2
|
| 23 |
Yellowstone County, Montana
|
2,633.3
|
| 24 |
Gallatin County, Montana
|
2,602.7
|
| 25 |
Missoula County, Montana
|
2,593.4
|
| 26 |
Meagher County, Montana
|
2,391.9
|
| 27 |
Ravalli County, Montana
|
2,390.8
|
| 28 |
Dawson County, Montana
|
2,371.9
|
| 29 |
Roosevelt County, Montana
|
2,354.8
|
| 30 |
Powell County, Montana
|
2,326.4
|
| 31 |
Teton County, Montana
|
2,272.4
|
| 32 |
Richland County, Montana
|
2,084.1
|
| 33 |
Carbon County, Montana
|
2,048.8
|
| 34 |
Toole County, Montana
|
1,915.7
|
| 35 |
Judith Basin County, Montana
|
1,869.8
|
| 36 |
Musselshell County, Montana
|
1,868.2
|
| 37 |
Sweet Grass County, Montana
|
1,855.2
|
| 38 |
Stillwater County, Montana
|
1,795.3
|
| 39 |
Prairie County, Montana
|
1,736.7
|
| 40 |
Granite County, Montana
|
1,727.4
|
| 41 |
Sheridan County, Montana
|
1,677.1
|
| 42 |
Jefferson County, Montana
|
1,656.3
|
| 43 |
Petroleum County, Montana
|
1,654.9
|
| 44 |
Pondera County, Montana
|
1,622.9
|
| 45 |
Fallon County, Montana
|
1,620.8
|
| 46 |
Lake County, Montana
|
1,490.2
|
| 47 |
Liberty County, Montana
|
1,430.0
|
| 48 |
Daniels County, Montana
|
1,426.1
|
| 49 |
Wheatland County, Montana
|
1,423.2
|
| 50 |
Mineral County, Montana
|
1,219.4
|
| 51 |
Broadwater County, Montana
|
1,192.5
|
| 52 |
Golden Valley County, Montana
|
1,175.3
|
| 53 |
Treasure County, Montana
|
977.4
|
| 54 |
Wibaux County, Montana
|
889.3
|
| 55 |
Deer Lodge County, Montana
|
736.5
|
| 56 |
Silver Bow County, Montana
|
718.5
|