Area Code 403 – Calgary
The phone area code for Calgary is 403 (international format +1 403). Browse local exchange codes (NXX) and carrier assignments below.
📞 Exchange Codes (NXX) for Area Code 403
Select a central office code to view local carrier data and detailed information
📍 Geographic Location of Calgary
Geographic Coverage and Administrative Jurisdiction
Area code 403 is a geographic numbering plan area (NPA) in the North American Numbering Plan (NANP), serving the province of Alberta, Canada. Historically, 403 covered the entire province, but due to population growth and demand for numbering resources, the province was subsequently divided. Today, 403 is assigned to the southern portion of Alberta, with the major metropolitan center being Calgary, the province's largest city. The code also serves surrounding communities, including Red Deer, Lethbridge, Medicine Hat, and Banff, as well as numerous rural municipalities and towns within the southern half of the province.
Administratively, the 403 NPA falls under the jurisdiction of the Canadian Radio-television and Telecommunications Commission (CRTC), which oversees numbering resource administration in Canada. The code is classified as a geographic area code, meaning that numbers are tied to a specific physical location, and the prefix is used for both landline and mobile services within the region.
Dialing Formats and Caller Instructions
For local callers within the 403 area code, the standard local dialing format is seven digits (the seven-digit subscriber number). However, as of 2021, Alberta implemented 10-digit local dialing (area code + seven-digit number) for all calls within the province, including those within the same area code. This change was necessary to accommodate the introduction of area code 368 as an overlay for the entire province. Therefore, even for calls to a number with the same area code, callers must dial the full 10-digit number.
For callers from outside the 403 area code but within Canada or the United States, the international format is: +1 403 XXX XXXX. For example, to call a business in Calgary from abroad, one would dial +1 403 555 0123. When dialing from within North America, the long-distance prefix '1' is used before the area code: 1 403 XXX XXXX.
Overlay Considerations and Numbering Changes
In 2021, the Canadian Numbering Administrator introduced area code 368 as an overlay for the entire province of Alberta, including the 403 region. This means that new telephone numbers in southern Alberta may be assigned either the 403 or 368 area code. As a result, all local calls within Alberta require 10-digit dialing, and callers must be aware that numbers with different area codes (403, 368, 587, 780, 825) may be local calls depending on the specific rate center. The overlay does not require any change to existing 403 numbers, but it does affect how new numbers are assigned and how calls are dialed.
Practical Examples for Callers
For a local caller in Calgary trying to reach a neighbor, the number would be dialed as 403 555 0123 (10 digits). For a caller in Vancouver, British Columbia, the number would be dialed as 1 403 555 0123. For an international caller from the United Kingdom, the number would be dialed as +1 403 555 0123. It is important to note that while 403 is a geographic code, many mobile numbers in the region use this area code, and they are not subject to geographic rating for wireless calls.