825 Area Code – Calgary, Alberta: Location, Time Zone & History

Alberta's original area code, 403, dates back to the very first North American numbering plan in 1947, when it covered the entire province plus Yukon, the Northwest Territories, and a sliver of what is now Nunavut. By January 1999 that territory had already been split once, with the province's northern two-thirds, including Edmonton, spun off as 780 while Calgary and the south kept 403. Rather than split again, Alberta chose overlays: 825 is a province-wide distributed overlay, layered on top of 403, 780, and 587 by Telecom Decision CRTC 2013-574 and put into service April 9, 2016.

825 followed 587, which had entered service in 2008 alongside Alberta's move to mandatory 10-digit local dialing, and it was itself followed by a fourth overlay, 368, activated in 2022. All four codes -- 403, 780, 587, and 825 -- now serve the same telephone numbers across Calgary, Edmonton, Red Deer, Fort McMurray, Grande Prairie, and Lethbridge without any geographic boundary between them.

The shared numbering plan area reflects Alberta's oil and gas economy, along with agriculture, technology, and tourism industries that draw on the same pool of numbers regardless of city. With roughly 4.26 million residents provincewide, 825 exists purely to keep pace with demand rather than to mark out new territory of its own.