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 southwestern 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 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 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 have also started serving the region.

History

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. 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.
The 548 area code was the second area code overlay for the 519 region. The new code was activated on June 4, 2015.Canadian Numbering Administrator advised the CRTC on October 12, 2011 that based on the current rate of expansion the current numbering system would be exhausted by January 2017. The CRTC in response developed a relief plan which set the framework for addressing the exhaustion and oversee the addition of an additional overlay number. Area code 382 has been reserved as a fourth code for the region.
The 519/226/548 territory covers a wide area, and no single municipality controlling a majority of the available numbers. In theory, therefore, the 226 overlay area code could have been introduced without breaking seven-digit dialing in any of the NPA 519 communities. This would, however, have required exchange numbers to be issued in a specific pattern. For instance, if 519-999-9999 were a Windsor number, the same number in the new area code, 226-999-9999, would have to be issued in London, Guelph, or some other community that would never be a local call to any point in the Windsor area.
While the implementation of 548 had the effect of allocating over 23 million numbers to a region of 2.6 million people, overlays have become the preferred method of relief in Canada, as they are an easy workaround for Canada's number allocation system. Canada does not use number pooling as a relief measure. Each CLEC is allocated blocks of 10,000 numbers for every rate centre where it offers service, even in the smallest hamlets. While most rate centres don't need nearly that many numbers, once a number is allocated to a carrier and rate centre, it can't be moved elsewhere, even to a larger rate centre.
Area code 382 has been set aside as a fourth area code for the region

Dialing areas