Area Code Overview

Area code 406 is a geographic telephone area code in Montana that went into service on January 1, 1947. The geographic regions covered by this area code overlay has a population of approximately 1,137,233.

Overlay and Dialing Rules

Area Code: 406
State: Montana
Type: General Purpose Code
In Service Date: January 1, 1947
Overlay Complex: 406
Local Dialing Plan: This area does require you to dial the area code when calling locally.

Estimated Number of Assigned Phone Numbers in Area Code 406

This area code is ranked 157th out of 363 nationwide in estimated assigned phone numbers. Within the state territory it serves, it is ranked 1st out of 1.

5,407,000

Estimated Service-Type Mix of Assigned Phone Numbers in Area Code 406

Total assigned 5,407,000

Wireless

1,517,000 assigned

28.06%

Wireline and VoIP

2,559,000 assigned

47.33%

Other / Unclassified

1,331,000 assigned

24.62%

Estimated Share of Wireless Numbers Originally Assigned to Each Carrier in Area Code 406

Estimated assigned wireless phone numbers: 1,517,000

Numbers may later be ported to another carrier, but this chart reflects original number assignment, not current subscriber share.

Verizon Wireless 940,000 (61.96%)

AT&T Wireless 365,000 (24.06%)

T-Mobile 175,000 (11.54%)

SAGEBRUSH CELLULAR, INC. 35,000 (2.31%)

Optimum Mobile 2,000 (0.13%)

Estimated Share of Wireline and VoIP Numbers Originally Assigned to Each Carrier in Area Code 406

Estimated assigned wireline and VoIP phone numbers: 2,559,000

Lumen 944,000 (36.89%)

Onvoy 822,000 (32.12%)

Bandwidth 167,000 (6.53%)

CHARTER IP ENABLED SERVICES, LLC 117,000 (4.57%)

TERRA NOVA TELECOM INC. 104,000 (4.06%)

Spectrum 92,000 (3.60%)

Telnyx 90,000 (3.52%)

MID-RIVERS TELEPHONE COOPERATIVE, INC. 63,000 (2.46%)

MCIMETRO ACCESS TRANSMISSION SERVICES LLC 33,000 (1.29%)

Airus 26,000 (1.02%)

ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 20,000 (0.78%)

Commio 19,000 (0.74%)

Other / Unclassified Assigned Numbering in Area Code 406

Estimated assigned other or unclassified phone numbers: 1,331,000

TRIANGLE TEL. COOP. ASSN., INC. 250,000 (18.78%)

NEMONT TEL COOP INC 200,000 (15.03%)

3 RIVERS TEL. COOP., INC. 193,000 (14.50%)

BLACKFOOT TEL. COOP., INC. 140,000 (10.52%)

MID-RIVERS TEL. COOP., INC. 130,000 (9.77%)

RANGE TEL COOP INC 60,000 (4.51%)

NORTHERN TEL. COOP., INC. 50,000 (3.76%)

SOUTHERN MONTANA TEL. CO. 50,000 (3.76%)

PROJECT TEL. CO., INC. 40,000 (3.01%)

RONAN TEL. CO. 40,000 (3.01%)

TELEPORT COMMUNICATIONS AMERICA MT - LLC 30,000 (2.25%)

BLACKFOOT COMMUNICATIONS, INC. - MT 26,000 (1.95%)

Cities and Towns in Area Code 406

Absarokee, Montana Alberton, Montana Alta, Montana Alzada, Montana Anaconda, Montana Arlee, Montana Ashland, Montana Augusta, Montana Avon, Montana Bainville, Montana Baker, Montana Belfry, Montana Belgrade, Montana Belt, Montana Big Sandy, Montana Big Sky, Montana Big Timber, Montana Bigfork, Montana Billings, Montana Birney, Montana Bloomfield, Montana Boulder, Montana Box Elder, Montana Bozeman, Montana Brady, Montana Bridger, Montana Broadus, Montana Broadview, Montana Brockton, Montana Browning, Montana Busby, Montana Butte, Montana Canyon Creek, Montana Carlyle, Montana Carter, Montana Cascade, Montana Charlo, Montana Chester, Montana Chinook, Montana Choteau, Montana Circle, Montana Clinton, Montana Clyde Park, Montana Colstrip, Montana Columbia Falls, Montana Columbus, Montana Condon, Montana Conrad, Montana Cooke City, Montana Culbertson, Montana Custer, Montana Cut Bank, Montana Dagmar, Montana Darby, Montana Decker, Montana Deer Lodge, Montana Denton, Montana Devon, Montana Dillon, Montana Divide, Montana Dixon, Montana Dodson, Montana Drummond, Montana Dupuyer, Montana Dutton, Montana East Glacier Park, Montana Ekalaka, Montana Elmo, Montana Ennis, Montana Ethridge, Montana Eureka, Montana Fairfield, Montana Fairview, Montana Fallon, Montana Finley Point, Montana Flaxville, Montana Forsyth, Montana Fort Benton, Montana Fort Peck, Montana Fort Shaw, Montana Fort Smith, Montana Frazer, Montana Frenchtown, Montana Froid, Montana Fromberg, Montana Gardiner, Montana Geraldine, Montana Geyser, Montana Gildford, Montana Glasgow, Montana Glendive, Montana Glentana, Montana Grant, Montana Grass Range, Montana Great Falls, Montana Hamilton, Montana Hardin, Montana Harlem, Montana Harlowton, Montana Harrison, Montana Haugan, Montana Havre, Montana Hays, Montana Helena, Montana Highwood, Montana Hingham, Montana Hinsdale, Montana Hobson, Montana Hopp, Montana Hot Springs, Montana Hungry Horse, Montana Huntley, Montana Hysham, Montana Jackson, Montana Joliet, Montana Joplin, Montana Jordan, Montana Judith Gap, Montana Kalispell, Montana Kevin, Montana Kremlin, Montana Lakeside, Montana Lambert, Montana Lame Deer, Montana Larslan, Montana Laurel, Montana Lavina, Montana Lewistown, Montana Libby, Montana Lima, Montana Lincoln, Montana Lindsay, Montana Livingston, Montana Lodge Grass, Montana Loma, Montana Malta, Montana Manhattan, Montana Marion, Montana Martinsdale, Montana Medicine Lake, Montana Melrose, Montana Melstone, Montana Melville, Montana Miles City, Montana Missoula, Montana Molt, Montana Moore, Montana Musselshell, Montana Nashua, Montana Neihart, Montana Noxon, Montana Olney, Montana Opheim, Montana Outlook, Montana Ovando, Montana Pablo, Montana Peerless, Montana Pendroy, Montana Philipsburg, Montana Plains, Montana Plentywood, Montana Plevna, Montana Polson, Montana Pompeys Pillar, Montana Poplar, Montana Potomac, Montana Power, Montana Rapelje, Montana Raynesford, Montana Red Lodge, Montana Reed Point, Montana Reserve, Montana Richey, Montana Ridge, Montana Rock Springs, Montana Ronan, Montana Rosebud, Montana Roundup, Montana Roy, Montana Rudyard, Montana Ryegate, Montana Saco, Montana Saint Ignatius, Montana Saint Mary, Montana Saint Regis, Montana Savage, Montana Scobey, Montana Seeley Lake, Montana Shelby, Montana Sheridan, Montana Sidney, Montana Somers, Montana Stanford, Montana Stevensville, Montana Stockett, Montana Sunburst, Montana Superior, Montana Swan Lake, Montana Sweet Grass, Montana Terry, Montana Thompson Falls, Montana Three Forks, Montana Townsend, Montana Troy, Montana Turner, Montana Twin Bridges, Montana Valier, Montana Victor, Montana Virginia City, Montana Warm Springs, Montana West Glacier, Montana West Glendive, Montana Westby, Montana White Sulphur Springs, Montana Whitefish, Montana Whitehall, Montana Whitewater, Montana Wibaux, Montana Wilsall, Montana Winifred, Montana Winnett, Montana Wisdom, Montana Wise River, Montana Wolf Creek, Montana Wolf Point, Montana Worden, Montana Wye, Montana Wyola, Montana

How These Figures Were Built

These figures are estimates based on public phone-number assignment records. They are meant to show the likely mix of assigned phone numbers associated with area code 406, not live customer counts.

Some providers may have assigned phone numbers tied to this area code even if they do not actively market or sell service locally. These figures reflect public number-assignment records, not confirmed local service availability.

They also do not reflect number portability at the individual phone-number level, so some numbers may now be used on a different network or by a different provider than the original assignment records suggest.

Population data and locality matching provided by GeoNames.

Last refreshed: April 15, 2026 6:22 pm