Area code 250Area code 403Area code 306Area code 701Area code 605Area code 307Area codes 208 and 986
Montana numbering plan area and area code (blue)

Area code 406 is the telephone area code in the North American Numbering Plan for the entire U.S. state of Montana. It has been Montana's only area code since the American Telephone and Telegraph Company created a nationwide telephone numbering plan in 1947.

As of 2013, there were 1.7 million lines served by 47 carriers; all but two wireline providers support local number portability (the exceptions are small rural independents Hot Springs Telephone Company and Northern Telephone Cooperative). Sufficient available codes for new exchanges in the 406 area code exist to meet anticipated demand until 2031; number pooling has been implemented in response to increased demand and inefficient use of 406 numbering resources.[1][2]

Prior to October 2021, area code 406 had telephone numbers assigned for the central office code 988. In 2020, 988 was designated nationwide as a dialing code for the National Suicide Prevention Lifeline, which created a conflict for exchanges that permit seven-digit dialing. This area code was therefore scheduled to transition to ten-digit dialing by October 24, 2021.[3]

Service area

The service area includes the following communities and their central office codes.

See also

References

  1. ^ Inbody, Kristen (27 Nov 2017). "In Montana, it's 406 exclusively until 2031". Great Falls Tribune. www.greatfallstribune.com. Retrieved 13 June 2023.
  2. ^ "Montana PSC Granted Authority to Implement Mandatory Number Pooling". fcc.gov. 12 December 2015. Archived from the original on 10 December 2017. Retrieved 7 May 2018.
  3. ^ "Transition to 10-digit dialing (for 988 as 3-digit access to National Suicide Prevention Hotline)" (PDF). North American Numbering Plan Administrator. January 8, 2021. Retrieved March 9, 2021.
  4. ^ North Parkman is served from wire centre DNRHWYMARS1 Archived 2014-10-19 at the Wayback Machine in Sheridan, WY
  5. ^ Ridge is served from HLTTWYXCRS1 Archived 2014-10-19 at the Wayback Machine Hulett, WY
  6. ^ Silvertip is served from POWLWYMARS1 Archived 2014-10-19 at the Wayback Machine Powell, WY
  7. ^ West Beach is served from BECHNDXADS1 Archived 2014-10-19 at the Wayback Machine in Beach, ND
  8. ^ West Camp Crook is served from CMCRSDXARL0 Archived 2014-10-19 at the Wayback Machine in Camp Crook, SD
  9. ^ West Squaw Gap is served from SQGPNDXARS5 Archived 2014-10-19 at the Wayback Machine Squaw Gap, ND

External links

Montana area codes: 406
North: 236/672/778, 250, 306, 403, 587/825/368, 639
West: 208/986 406 East: 605, 701
South: 307
Alberta area codes: 403, 587/825/368, 780
British Columbia area codes: 236/672/778, 250, 604
Saskatchewan area codes: 306, 639
Idaho area codes: 208/986
North Dakota area codes: 701
South Dakota area codes: 605
Wyoming area codes: 307
Lists of area codes in the North American Numbering Plan
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