Area codes 204, 431, and 584

When the American Telephone and Telegraph Company (AT&T) designed the first comprehensive North American telephone numbering plan in the 1940s, Manitoba was designated as a single numbering plan area (NPA) with area code 204.

In 2009, the Canadian Numbering Administrator forecast the proliferation of cell phones, particularly in and around Winnipeg, would exhaust the number of unallocated central office prefixes within a few years, even though the province has only 1.2 million people. An area code provides about 7.8 million telephone numbers, but Canada uses an allocation scheme that allots all ten thousand numbers of a central office prefix to each competitive local exchange carriers even for the smallest hamlets. Canada does not implement number pooling.

In July 2010, the Canadian Radio-television and Telecommunications Commission approved a province-wide overlay with area code 431 for implementation in November 2012.^[1] On July 30, 2012, 10-digit dialing became mandatory throughout the province.^[2]

Area code 584 was reserved as a third area code for the region in February 2017.^[3] It was implemented on October 29, 2022.^[4][5][6]

The incumbent local exchange carrier for the area codes is Bell MTS.

• Telephone numbers in Canada