Area codes 778, 236, and 672 are telephone area codes in the North American Numbering Plan (NANP) for the Canadian province of British Columbia. They form an overlay complex with area code 604, which serves only a small southwestern section, the Lower Mainland, of the province (including Vancouver), and area code 250, which serves the rest of the province.
The area codes also serve the small United States community of Hyder, Alaska, which is located along the Canada–United States border near the town of Stewart.
Area code 257 is scheduled for overlay with the existing area codes in the numbering plan area for relief on May 24, 2025.[1]
Area code 604 had served as British Columbia's sole area code for 53 years since the establishment of the North American Numbering Plan in 1947. In 1997, area code 250 was installed for Vancouver Island and the Interior, while area code 604 was restricted to serve Vancouver and the Lower Mainland. Intended as a long-term solution, the proliferation of telephone service in the area required additional central office code relief within only four years. While telephone numbers tended to be used up fairly quickly in the immediate Vancouver area due to its rapid growth, the number allocation problem was particularly severe in the Lower Mainland, which is home to most of the province's landlines and cell phones. Area code 778 was created on November 3, 2001, as a concentrated overlay for the two largest regional districts in the Lower Mainland, Metro Vancouver and the Fraser Valley Regional District. The rest of the Lower Mainland continued to use only 604.[2] Nonetheless, the implementation of 778 made ten-digit dialing mandatory across the Lower Mainland.
In early 2007, the Canadian Radio-television and Telecommunications Commission (CRTC) faced the prospect that area code 250 would be exhausted in early 2008. Relief proposals included a geographic split that would have retained area code 250 for the interior of the province, with Vancouver Island switching to a new area code. An alternative was to expand area code 778 to the 250 numbering plan area, or concentrated overlays for a part of 250.[3] The CRTC concluded that there was not enough time to implement a split before exhaustion, and the major telecom providers in the territory contended that an overlay would be far easier to implement. Telus and other carriers wanted to spare their Vancouver Island customers the expense and burden of changing telephone numbers for a second time in a decade.[4] Accordingly, the CRTC announced on June 7, 2007, that 778 would become an overlay for the entire province effective July 4, 2007.[5] Overlays have become the preferred method of relief in Canada, and no area codes have been split in the country since 1999.
As of June 23, 2008, ten-digit dialing became mandatory across British Columbia; attempting to use only seven digits triggers an intercept message reminding callers of the rules. After September 12, 2008, seven-digit dialing ceased to function.[6]
Within another four years, 604, 250, and 778 were close to exhaustion once again, requiring the addition of area code 236 for the province on June 1, 2013.[7]
In 2019, area codes 604, 250, 778, and 236 were expected to reach certain exhaustion thresholds in May 2020. The CRTC ordered the introduction of a third overlay code for the province, 672, which was activated on May 4, 2019.[8][9]