Understanding Area Codes
Everything you need to know about global telephone area codes.
Where are area codes used?
Area codes are an essential part of the global telecommunications infrastructure. We provide comprehensive data for the United States, Canada, and the United Kingdom. While the US and Canada share the North American Numbering Plan (NANP), other nations like the UK utilize their own distinct numbering systems. Area codes are tied to specific locations—cities, regions, or entire states—while non-geographic codes serve special purposes like toll-free calling.
Format of a Telephone Number
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Assignment & The Growing Need
Phone numbers are assigned by national regulatory bodies. As populations grow and the number of devices (mobile phones, tablets, IoT devices) explodes, the demand for new phone numbers has skyrocketed. Many regions that once relied on a single area code now require multiple codes to satisfy the demand.
Area Code Complexity Over Time
Splits vs. Overlays
Historically, when an area code ran out of numbers, the region was split geographically. Half the residents kept the old code, while the other half were forced to switch to a new one.
Today, the preferred method is an Overlay. A new area code is added to the same geographic region. Existing numbers don't change, but 10-digit dialing becomes mandatory for local calls.
Requires 50% of users to change their number. Disruptive and costly for businesses.
No number changes required. Seamless integration of new lines.
Number Pooling & Conservation
To extend the life of the numbering plan, Number Pooling was introduced. Instead of assigning blocks of 10,000 numbers to a single carrier (an entire exchange), numbers are now assigned in smaller blocks of 1,000. This drastic reduction in waste has delayed the exhaustion of many area codes by decades.
Modern Usage & Non-Geographic Codes
Dominant drivers of new number demand.
800, 833, 844, 855, 866, 877, 888.
Smart cars, meters, and alarms.