Where Is Area Code 406?
Area code 406 serves all of Montana, a state in the Mountain West. Billings is the primary city, and the code covers Montana’s cities, small towns, rural areas, and tribal communities.
The code covers all 56 Montana counties. Major population centers include Billings in Yellowstone County, Missoula in Missoula County, Great Falls in Cascade County, Bozeman in Gallatin County, Helena in Lewis and Clark County, and Kalispell in Flathead County.
Notable features within the 406 territory include Glacier National Park, the Montana portion of Yellowstone National Park, the Rocky Mountains, and the Great Plains. Billings sits beside the Yellowstone River and the Rimrocks, a series of sandstone cliffs above the city.
Cities and Communities in the 406 Area Code
- Anaconda, Deer Lodge County
- Baker, Fallon County
- Belgrade, Gallatin County
- Billings, Yellowstone County
- Big Timber, Sweet Grass County
- Bozeman, Gallatin County
- Browning, Glacier County
- Butte, Silver Bow County
- Chinook, Blaine County
- Choteau, Teton County
- Columbia Falls, Flathead County
- Columbus, Stillwater County
- Conrad, Pondera County
- Cut Bank, Glacier County
- Deer Lodge, Powell County
- Dillon, Beaverhead County
- East Helena, Lewis and Clark County
- Ennis, Madison County
- Eureka, Lincoln County
- Fairfield, Teton County
- Fort Benton, Chouteau County
- Forsyth, Rosebud County
- Glasgow, Valley County
- Glendive, Dawson County
- Great Falls, Cascade County
- Hamilton, Ravalli County
- Hardin, Big Horn County
- Havre, Hill County
- Helena, Lewis and Clark County
- Kalispell, Flathead County
- Laurel, Yellowstone County
- Lewistown, Fergus County
- Libby, Lincoln County
- Livingston, Park County
- Malta, Phillips County
- Manhattan, Gallatin County
- Miles City, Custer County
- Missoula, Missoula County
- Plains, Sanders County
- Plentywood, Sheridan County
- Polson, Lake County
- Red Lodge, Carbon County
- Ronan, Lake County
- Roundup, Musselshell County
- Shelby, Toole County
- Sidney, Richland County
- Stevensville, Ravalli County
- Superior, Mineral County
- Thompson Falls, Sanders County
- Three Forks, Gallatin County
- Townsend, Broadwater County
- Troy, Lincoln County
- Virginia City, Madison County
- West Yellowstone, Gallatin County
- Whitehall, Jefferson County
- Whitefish, Flathead County
- Wolf Point, Roosevelt County
History of Area Code 406
Area code 406 was assigned in 1947 as Montana’s original North American Numbering Plan area code. It was one of the original 86 area codes created for the telephone numbering system in the United States and Canada.
Montana has continued to use one statewide area code as landline, mobile, and other telephone services expanded. Montana has not added a second area code through a split or overlay, so 406 still covers the entire state.
Key Facts About Area Code 406
- Area code 406 is a geographic area code for Montana, with Billings as its primary city.
- Area code 406 covers all 56 counties in Montana.
- The 2020 U.S. Census counted 1,084,225 residents in Montana, which is the approximate resident population within the code’s territory.
- The North American Numbering Plan assigned area code 406 in 1947 as one of its original area codes.
- Area code 406 has not been split or overlaid with another Montana area code.
- Montana State University is in Bozeman, and the University of Montana is in Missoula.
- Glacier National Park and Montana’s portion of Yellowstone National Park are within the 406 geographic area.
Frequently Asked Questions
What state is area code 406 in?
Area code 406 is in Montana (MT).
What major cities use area code 406?
Major cities using area code 406 include Billings, Missoula, Great Falls, Bozeman, Helena, Butte, and Kalispell.
What time zone is area code 406 in?
Area code 406 uses Mountain Time.
Is area code 406 a toll-free number?
No. Area code 406 is a geographic area code, not a toll-free code.