1. World Map/
  2. North America/
  3. US/
  4. Area Codes/
  5. Area Code 406

Where Is Area Code 406?

Area code 406 is found in the US state of Montana. Servicing the entire state, area code 406 includes the city of Billings (population: 131508), and all 56 counties of Montana.

Located in the Mountain time zone, area code 406 is on the same time as Phoenix, AZ.

Area code 406 was brought into effect on January 1, 1947.

Map of  with area code 406 highlighted

Counties in Area Code 406

  • Beaverhead,
  • Big Horn,
  • Blaine,
  • Broadwater,
  • Carbon,
  • Cascade,
  • Chouteau,
  • Custer,
  • Daniels,
  • Dawson,
  • Deer Lodge,
  • Fallon,
  • Fergus,
  • Flathead,
  • Gallatin,
  • Glacier,
  • Granite,
  • Hill,
  • Jefferson,
  • Lake,
  • Lewis and Clark,
  • Liberty,
  • Lincoln,
  • Madison,
  • McCone,
  • Meagher,
  • Mineral,
  • Missoula,
  • Musselshell,
  • Park,
  • Phillips,
  • Pondera,
  • Powder River,
  • Powell,
  • Ravalli,
  • Richland,
  • Roosevelt,
  • Rosebud,
  • Sanders,
  • Sheridan,
  • Silver Bow,
  • Stillwater,
  • Sweet Grass,
  • Teton,
  • Toole,
  • Valley,
  • Wheatland,
  • Wibaux,
  • Yellowstone.

Most Populous Cities in Area Code 406

City County City Population Time Zone
Billings Yellowstone 131,508 MST
Missoula Missoula 92,381 MST
Great Falls Cascade 72,430 MST
Bozeman Gallatin 60,973 MST
Helena Lewis and Clark 54,818 MST
Kalispell Flathead 50,078 MST
Butte Silver Bow 33,695 MST
Belgrade Gallatin 18,811 MST
Columbia Falls Flathead 13,603 MST
Hamilton Ravalli 13,183 MST
Havre Hill 12,849 MST
Whitefish Flathead 12,685 MST
Livingston Park 11,827 MST
Miles City Custer 11,588 MST
Laurel Yellowstone 11,253 MST
Polson Lake 9,995 MST
Libby Lincoln 9,757 MST
Stevensville Ravalli 9,713 MST
Lewistown Fergus 8,986 MST
Anaconda Deer Lodge 8,870 MST
Glendive Dawson 8,567 MST
Sidney Richland 8,158 MST
Dillon Beaverhead 8,049 MST
Browning Glacier 7,898 MST
Bigfork Flathead 7,739 MST

Note: The above list is based off of the top 25 most populous cities in the area code as per 2012 United States Census Bureau estimates.

View all United States Area Codes.

Trending on WorldAtlas

This page was last updated on July 3, 2015.