Area codes 519, 226, and 548

Area codes 519, 226 and 548 are the telephone area codes serving most of southwestern Ontario.

The main area code, 519, was created in 1953 from the western portion of 416 and the northern portion of 613. In 1957, parts of 519 and 613 formed 705. It is mostly bounded by area code 905, except for Simcoe County which is bordered by 705. It was overlaid with the new area code 226 on October 21, 2006, at which time ten-digit dialling became mandatory. Area code 226 is Canada's 25th geographical area code (not including area code 600). Area code 548 was added as a third overlay beginning on June 4, 2015. Area code 382 has been reserved as a fourth code for the region.

The primary ILEC (Incumbent Local Exchange Carrier) in 519/226/548 is Bell Canada, with numerous other small independent companies that covered vast tracts of rural Ontario. Since competition for service was mandated in 1997, numerous CLECs (Competitive Local Exchange Carrier) have also started serving the region.

The 226 area code was first proposed as a result of an NPA exhaustion study conducted in the 1990s. The issue was raised with the CRTC by telecommunications firms and SAIC Canada, and in 1992 a relief plan was approved (Telecom Decision CRTC 2002-25). Although it primarily accepted the industry proposal, the CRTC required a permissive dialling period of four months, with consistent network announcements to consumers, instead of the proposed two-month period. On April 15, 2003, the committee recommended delaying the introduction of the 226 area code from February 19, 2005 to October 21, 2006, primarily as a result of updated forecasts of the 519 NPA exhaustion projections.

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