406 Area Code 🌍☎️

The most populous cities in area code 406 are: Billings, Missoula, Great Falls, Helena, and Bozeman.

Other cities in the 406 area code include: Kalispell, Butte, Sidney, Miles City, Havre, Glendive, Livingston, Lewistown, Ronan, Ashland, Dillon, Hamilton, Hardin, Shelby, Anaconda, Laurel, Whitefish, Polson, Columbia Falls, Columbus, Bigfork, Cut Bank, Wolf Point, Conrad, Belfry, Glasgow, Red Lodge, Libby, Townsend, Baker, Forsyth, Manhattan, Eureka, Boulder, Browning, Ennis, Wilsall, Saint Regis, Belgrade, Malta, Roundup, Divide, Deer Lodge, Scobey, Culbertson, Fairfield, Cascade, Superior, Busby, Wibaux, Broadus, Fromberg, Nashua, Plevna, Wyola, Fallon, Rosebud, Alzada, West Yellowstone, Seeley Lake, Big Timber, Thompson Falls, Lakeside, East Helena, Three Forks, Stevensville, Absarokee, Clinton, White Sulphur Springs, Whitehall, Saint Ignatius, Chester, Marion, Bridger, Vaughn, Gallatin Gateway, Worden, Victor, Darby, Big Sandy, Joliet, Circle, Huntley, Charlo, Ekalaka, Savage, Jordan, Medicine Lake, Elmo, Lavina, Brady, Richey, Hinsdale, Brockton, Froid, Lima, Roy, Grass Range, Sweet Grass, Musselshell, Opheim, Loma, Lambert, Zortman, Molt, Pendroy, Rollins, Wolf Creek, Frenchtown, Somers, Alberton, Silver Gate, Crow Agency, Plentywood, Bonner, Clancy, Fort Benton, Gardiner, Chinook, Corvallis, Park City, Harlem, Terry, Poplar, Plains, Lincoln, Sheridan, Troy, Belt, Philipsburg, Arlee, Valier, Hot Springs, Hysham, Stanford, Condon, Roberts, Drummond, Dutton, Lodge Grass, Sunburst, Geraldine, Frazer, Hobson, Sand Coulee, Saco, Bainville, Highwood, Virginia City, Joplin, Reed Point, Denton, Dixon, Moore, Fort Peck, Ryegate, Broadview, Westby, Winifred, Winnett, Power, Rudyard, Fort Shaw, Conner, Birney, Carter, Kremlin, Gildford, Hingham, Outlook, Whitewater, Wisdom, Box Elder, Turner, Martinsdale, Ovando, Judith Gap, Garrison, Flaxville, Saint Xavier, Neihart, Angela, Bighorn, Bloomfield, Canyon Creek, Capitol, Dagmar, Decker, Dodson, Essex, Galata, Jackson, Larslan, Lindsay, Melville, Norris, Olive, Peerless, Polaris, Rapelje, Raynesford, Two Dot, Whitetail, Wise River, Lolo, Choteau, Emigrant, Twin Bridges, Noxon, and Geyser.

Billings is the largest city in the state of Montana, and is the principal city of the Billings Metropolitan Area with a population of 166,855. It has a trade area of over half a million people. Billings is located in the south-central portion of the state and is the seat of Yellowstone County, which had a 2015 population of 157,048. The 2015 Census estimates put the Billings population at 110,263, making it the only city in Montana with over 100,000 people. The city is experiencing rapid growth and a strong economy; it has had and is continuing to have the largest growth of any city in Montana. Parts of the metro area are seeing hyper growth. From 2000 to 2010 Lockwood, an eastern suburb of the city, saw growth of 57.8%, the largest growth rate of any community in Montana. Billings has avoided the economic downturn that affected most of the nation 2008–2012 as well as avoiding the housing bust. With the Bakken oil development in eastern Montana and western North Dakota, the largest oil discovery in U.S. history, as well as the Heath shale oil discovery just north of Billings, the city's already rapid growth rate is escalating. Billings was nicknamed the "Magic City" because of its rapid growth from its founding as a railroad town in March 1882. The city is named for Frederick H. Billings, a former president of the Northern Pacific Railroad. With one of the largest trade areas in the United States, Billings is the trade and distribution center for much of Montana east of the Continental Divide, Northern Wyoming, and western portions of North Dakota and South Dakota. Billings is also the retail destination for much of the same area. With more hotel accommodations than any area within a five-state region, the city hosts a variety of conventions, concerts, sporting events, and other rallies. Area attractions include Pompey's Pillar, Pictograph Cave, Chief Plenty Coups State Park, Zoo Montana, and Yellowstone Art Museum. Within 100 miles are Little Bighorn Battlefield National Monument, Bighorn Canyon National Recreation Area, Red Lodge Mountain Resort, and the Beartooth Highway, which links Red Lodge to Yellowstone National Park.

Missoula Listen i / m ᵻ ˈ z uː l ə / is a city in the U.S. state of Montana and is the county seat of Missoula County. It is located along the Clark Fork River near its confluences with the Bitterroot and Blackfoot Rivers in western Montana and at the convergence of five mountain ranges, thus is often described as the "hub of five valleys". In 2015 , the United States Census Bureau estimated the city's population at 71,022 and the population of the Missoula Metropolitan Area at 114,181. In the 1990s, Missoula overtook Great Falls as Montana’s second‑largest city, behind Billings. Missoula is home to the University of Montana, a public research university.Missoula was founded in 1860 as Hellgate Trading Post while still part of Washington Territory. By 1866, the settlement had moved east, 5 miles (8 km) upstream, and renamed Missoula Mills, later shortened to Missoula. The mills provided supplies to western settlers traveling along the Mullan Road. The establishment of Fort Missoula in 1877 to protect settlers further stabilized the economy. The arrival of the Northern Pacific Railway in 1883 brought rapid growth and the maturation of the local lumber industry. In 1893, the Montana Legislature chose the city as the site for the state's first university. Along with the U.S. Forest Service headquarters founded in 1908, lumber and the university remained staples of the local economy for the next hundred years. By the 1990s, Missoula's lumber industry had gradually disappeared, and as of 2009 , the city's largest employers were the University of Montana, Missoula County Public Schools, and Missoula's two hospitals. The city is governed by a mayor–council government with twelve city council members, two from each of the six wards. In and around Missoula are 400 acres (160 ha) of parkland, 22 miles (35 km) of trails, and nearly 5,000 acres (2,000 ha) of open-space conservation land with adjacent Mount Jumbo home to grazing elk and mule deer during the winter. The city is also home to both Montana's largest and its oldest active breweries as well as the Montana Grizzlies, one of the strongest college football programs in the Division I Football Championship Subdivision of the National Collegiate Athletic Association (NCAA). Notable residents include the first woman in the U.S. Congress, Jeannette Rankin, and the United States' longest-serving Senate Majority Leader, Mike Mansfield.

Great Falls is a city in and the county seat of Cascade County, Montana, United States. The 2015 census estimate put the population at 59,638. The population was 58,505 at the 2010 census. It is the principal city of the Great Falls, Montana Metropolitan Statistical Area, which encompasses all of Cascade County and has a population of 82,278. Great Falls was the largest city in Montana from 1950 to 1970, when Billings surpassed it. Great Falls remained the second largest city in Montana until 2000, when it was passed by Missoula. Since then Great Falls has been the third largest city in the state. Great Falls takes its name from the series of five waterfalls in close proximity along the upper Missouri River basin that the Lewis and Clark Expedition had to portage around over a ten-mile stretch; the effort required 31 days of arduous labor during the westward leg of their 1805-06 exploration of the Louisiana Purchase and to the Pacific Northwest Coast of the Oregon Country. Each falls sports a hydroelectric dam today, hence Great Falls is nicknamed "the Electric City". Currently there are two undeveloped parts of their portage route; these are included within the Great Falls Portage, a National Historic Landmark.The city is home to the C. M. Russell Museum Complex, the University of Great Falls, Great Falls College Montana State University, Giant Springs, the Roe River (claimed to be the world's shortest river), the Montana School for the Deaf and the Blind, the Great Falls Voyagers minor league baseball (formerly known as the Great Falls White Sox and before that as the Dodgers and Giants respectively) team, and Malmstrom Air Force Base. The local newspaper is the Great Falls Tribune. A Coldwell Banker Home Price Comparison Index listed Great Falls as the most affordable area of 348 markets in the US, Canada, and Puerto Rico.

The 406 area code lies within the Mountain Daylight Time Zone (or MDT). The current time in Mountain Daylight Time is 05:20 AM on Mar 10, 2026.