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]
The service area includes the following communities and their central office codes.
Ten-digit dialing is a telephone dialing procedure in the countries and territories that are members of the North American Numbering Plan (NANP). It is the practice of including the area code of a telephone number when dialing to initiate a telephone call. When necessary, the ten-digit number may be prefixed with the trunk code 1, which is referred to as 1+10-digit dialing or national format.
Area code 941 is a telephone area code in the North American Numbering Plan for a west-central coastal portion of the U.S. state of Florida. Introduced on March 3, 1996, the numbering plan area includes the counties of Manatee, Sarasota, and Charlotte, areas along the Sun Coast of southwestern Florida, USA. It is the area code for North Port-Bradenton-Sarasota, Florida Metropolitan Statistical Area.
Area code 775 is a Nevada telephone area code in the North American Numbering Plan. It was split from area code 702 on December 12, 1998, and covers the entire state except for Clark County, which retained area code 702 after the split. Major cities in this area code include Reno, Carson City, Elko and Pahrump. While it appears to be rural, more than 80 percent of its numbers are located in the far western portion, around Reno and Carson City.
Area code 352 is a telephone area code in the North American Numbering Plan for the area around Gainesville, Florida. It was split from area code 904 in 1995.
Area code 907 is a telephone area code in the North American Numbering Plan (NANP) for the U.S. state of Alaska, except for the small southeastern community of Hyder, which uses area codes 236, 250, and 778 of neighboring Stewart, British Columbia.
Area codes 910 and 472 are telephone area codes in the North American Numbering Plan (NANP) for southeastern North Carolina. The area codes form an overlay for a numbering plan area (NPA) that includes the cities of Wilmington, Jacksonville, Laurinburg, Lumberton and Fayetteville. Area code 910 was established in 1993, and 472 was added to the same area in October 2022.
Area code 302 is a telephone area code in the North American Numbering Plan (NANP) for the U.S. state of Delaware. It is Delaware's only area code, and was assigned in 1947 as one of the original North American area codes.
Area code 616 is the telephone area code in the North American Numbering Plan (NANP) for Greater Grand Rapids, Michigan. The numbering plan area also includes the towns of Holland, Greenville, and Grand Haven. This comprises all of Kent and Ottawa counties, and parts of neighboring counties, including the western and central parts of Ionia County. It was one of the original North American area codes created in 1947.
Area code 530 is a telephone area code in the North American Numbering Plan (NANP) in northeastern and Northern California. It was created in 1997 in an area code split of 916.
Area code 505 is a telephone area code in the North American Numbering Plan (NANP) for the U.S. state of New Mexico. Its numbering plan area (NPA) comprises the northwestern and central portions of the state, including the Albuquerque metropolitan area, Gallup, Santa Fe, and Farmington. The area code is one of the original North American area codes established in October 1947. Until October 7, 2007, it served the entire state.
Area code 915 is a telephone area code in the North American Numbering Plan for the area around El Paso, Texas, U.S. It is one of the original North American area codes established in October 1947, when it was assigned to the north-western part of the state, north of Austin and west of Fort Worth, and stretched from the Oklahoma border to the Mexican border.
Area code 509 is the telephone area code in the North American Numbering Plan (NANP) for the eastern part of the U.S. state of Washington. The numbering plan area (NPA) roughly comprises the state east of the Cascade Mountains, and includes Spokane, the Tri-Cities, Ellensburg, Yakima, Walla Walla, and Wenatchee. The area code was assigned in a split of area code 206 in 1956.
Area code 660 is the telephone area code in the North American Numbering Plan (NANP) for the northern and western part of the U.S. state of Missouri. It was created on October 12, 1997, in a split of the 816 numbering plan area (NPA)
Area code 989 is a telephone area code in the North American Numbering Plan for Central Michigan, the northeastern Lower Peninsula, and portions of the Thumb. It is the highest-numbered area code in use in the North American Numbering Plan (NANP), as well as the highest possible under the current system, in which a middle digit of 9 is forbidden.
Area code 605 is the telephone area code in the North American Numbering Plan for the entire U.S. state of South Dakota. The numbering plan area was designated in 1947, when the American Telephone and Telegraph Company (AT&T) devised a comprehensive telephone numbering plan for the United States and Canada.
Area code 501 is a telephone area code in the North American Numbering Plan (NANP) for central Arkansas, including Little Rock and most of its suburbs. The numbering plan area (NPA) comprises most communities in Cleburne, Conway, Faulkner, Garland, Hot Spring, Lonoke, Perry, Pulaski, Saline, White and Van Buren counties.
Area code 620 covers telephone exchanges in most of southern Kansas. It was created as the result of a split from 316 on February 3, 2001. The area code stretches across the southern half of the state, from the Colorado border in the west to the Missouri border in the east. It completely surrounds 316, which now only serves Wichita and its inner suburbs, making it one of the six pairs of "doughnut area codes" in the numbering plan. Permissive dialing of 316 across southern Kansas continued until November 3, 2001.
Area code 417 is a telephone area code in the North American Numbering Plan (NANP) for the southwestern quadrant of Missouri, including the cities of Branson, Carl Junction, Carthage, Joplin, Lebanon, Neosho, Nixa, Ozark, Springfield, and West Plains. Area code 417 was created in 1951 as a split from area code 816.
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 |