Discover the 5 Fastest-Growing Counties in Montana

Tulips in Montana
© SirWeAre/

Written by Oak Simmons

Updated: July 5, 2023

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It’s no surprise that Montana’s unofficial nickname is “Big Sky Country.” At a whopping 147,070 square miles, Montana is an incredibly vast state. In fact, Montana is the fourth-largest state in the United States by total area. However, a large area does not necessarily mean a large population. In spite of Montana’s size, the state’s population is relatively small. Montana currently ranks as the third-least-densely populated state, and the eighth-least populated state overall. However, Montana’s population is growing quickly, so these rankings could change in the future. According to United States census data, Montana ranked as the second-fastest-growing state between 2020-2022, just behind its neighbor Idaho. Which of Montana’s 56 counties is seeing the most population growth? This article will explore the five fastest-growing counties in Montana, according to U.S. census data.

Glacier National Park

Glacier National Park, in Flathead and Glacier Counties, is one of the eight National Parks in Montana.


Terrain and Population

Montana is a vast landlocked state in the Mountain West region of the United States. Montana shares a border with Idaho to the west, Wyoming to the south, North and South Dakota to the east, and Canada to the north. The geography of Montana is rich with mountains, prairies, and badlands. Geographically, there is a stark contrast between the western and eastern sides of Montana. Western Montana is primarily mountainous, with the northern Rocky Mountains running through it and forming the Continental Divide. East of the Rockies, Montana is largely prairie and badlands. The state is known for its vast and beautiful wilderness. In fact, Montana is home to eight national parks and over 170 state parks. Montana’s natural beauty makes it a popular place for tourism, and it is also becoming a more popular place to live.

counties in Montana

Montana’s population increased by 38,670 from 2020 to 2022. The state saw a 1.7 percent increase in population from 2020 to 2021 and a 1.5 percent increase from 2021 to 2022. Since Montana is a large and geographically diverse state, we will explore the counties that have grown the most in recent years. The five fastest-growing counties in Montana are Flathead, Gallatin, Yellowstone, Ravalli, and Missoula.

Flathead County

Fishing Pier Extending Onto Foys Lake, Kalispell, Montana, USA

The pier at Foy Lake is a popular fishing spot near Kalispell, MT.

©Billy McDonald/

Flathead County, located in Northwestern Montana, saw the most population growth from 2020 to 2022 of any Montana county. During that span, the population grew from 104,862 to 111,814, an increase of 6,952 people. Flathead County is the fourth-most populous county in Montana. Kalispell is the largest city in Flathead County, with a population of 24,558 according to the 2020 census.

Flathead County is a fantastic place for people who enjoy spending time outdoors. A mere six percent of the land mass in Flathead County is developed or available for development. The remaining 94 percent is national forests, state forests, agricultural land, or corporate timber land. Notably, Flathead County is home to the western part of Glacier National Park. Additionally, the county includes parts of the Flathead, Kootenai, and Lolo National Forests. The northern border of Flathead County is shared with British Columbia, a Canadian province known for its beauty and vast wilderness. Due to the incredible natural landscape of Flathead County, tourism is a booming industry. The county sees a large influx of people every summer. In fact, according to the Flathead County government, the county’s population grows by an astounding 40 percent during the months of June through August.

Gallatin County

The hills of Bozeman, Montana are full of paths for walking, running and other fitness activities.  There are picturesque views of the city and the mountains.  There are benches to enjoy the view.

The hills of Bozeman, MT are full of walking paths featuring picturesque views of the city and mountains.


Gallatin County is the second-fastest-growing county in Montana. It is located in Southwestern Montana. From 2020 to 2022, the population grew by 5,272 people, increasing from 119,585 to 124,857. Gallatin County is the second-most populous county in Montana. The county shares a border with Idaho to the south and Wyoming to the east. Bozeman is the largest city in Gallatin County, with a population of 53,293 according to the 2020 census.

In Gallatin County, as is true of Montana in general, outdoor recreation is a big attraction for residents and visitors. Gallatin County is home to a popular northern entrance to Yellowstone National Park, in the town of West Yellowstone. It is also home to the Big Sky Resort, the second-largest ski resort in the United States, which is an hour south of Bozeman.

Yellowstone County

Aerial of Downtown Billings Montana in the midwestern United States.

Billings is the most populous city in Montana, with a population of 117,116 in 2020.


Yellowstone County, in Southern Montana, is the third-fastest-growing county in Montana. From 2020 to 2022, the population of Yellowstone County grew by 4,656 people, increasing from 165,196 to 169,852. Yellowstone County is the most populous county in Montana. Additionally, Yellowstone County is home to Billings, the most populous city in Montana. According to the 2020 census, Billings has a population of 117,116.

Yellowstone County is named after the Yellowstone River, the river from which Yellowstone National Park also gets its name. However, the county is not actually home to or bordering Yellowstone National Park.

Billings, MT, is a major trade and distribution center for eastern Montana. The city was founded in 1882 as a railroad town and was later nicknamed the “Magic City” due to its rapid growth. The Crow Indian Reservation is ten miles southeast of Billings. This reservation is home to the Apsáalooke people, also known as the Crow people. The Apsáalooke name for Billings is ‘Ammalapáshkuua’, which means ‘where they cut wood’, a reference to a large sawmill that settlers built in the area.

Ravalli County

Drone view of the bitterroot mountain range in Hamilton Montana

Hamilton is a small city in the Bitterroot Valley. The beautiful Bitterroot Mountains lie outside the city.


Ravalli County, in Western Montana, is the fourth-fastest-growing county in Montana. The population of Ravalli County grew by 2,889 people from 2020 to 2022, increasing from 44,409 to 47,298. Hamilton is the largest city in Ravalli County, with a population of 4,659 according to the 2020 census. Ravalli County shares a border with Idaho on its western side.

Ravalli County is in the Bitterroot Valley, which sits between the Sapphire Mountains to the east and the Bitterroot Mountains to the West. The valley and mountains are named for the bitterroot flower, which grows there. In 1895, bitterroot became the official state flower of Montana. Ravalli County is named after Antony Ravalli, a Jesuit priest who came to the area in 1845.

Missoula County

This is an aerial panoramic next the Higgins Street Bridge in Missoula, Montana on a beautiful fall day in Western Montana.  You can see the M on Mount Sentinel and L on Mount Jumbo.

The Clark Fork River runs through the city of Missoula, MT. Missoula is the seat of Missoula County.

©Keegan Connell/

Missoula County is the fifth-fastest-growing county in Montana. It is located in Western Montana, on the border of Idaho. From 2020 to 2022, the population of Missoula County grew by 2,704 people, increasing from 118,337 to 121,041. Missoula County is the third-most populous county in Montana. The largest city is Missoula, with a population of 73,489 according to the 2020 census.

Missoula County is in the northern Rocky Mountains. The county includes parts of the Lolo, Bitterroot, and Flathead National Forests. Missoula County is also home to the Rattlesnake National Recreation Area, which is four miles north of Missoula. This area features a large and extensive trail system, which is popular among Missoula residents. Two major rivers run through the county, the Clark Fork and Bitterroot Rivers. Missoula County is ecologically diverse and abundant in wildlife.

The name Missoula comes from ‘nmesuletkw’, the Salish word for the Clark Fork River. Nmesuletkw means ‘place of frozen water’. The Salish people are one of the multiple native groups from the area.

Summary of the 5 Fastest-Growing Counties in Montana

RankCountyPopulation growth from 2020- 2022Largest City
1Flathead County6,952 Kalispell
2Gallatin County5,272Bozeman
3Yellowstone County 4,656Billings
4Ravalli County2,889Hamilton
5Missoula County2,704Missoula

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About the Author

Oak Simmons is a writer at A-Z Animals primarily covering North American wildlife and geography. They graduated from the University of California, Santa Cruz in 2018 with a Bachelor of Science in Ecology and Evolutionary Biology. A resident of Washington state, Oak enjoys tracking mammals and watching birds.

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