List of area code overlays

An area code overlay is a numbering plan area (NPA) in the North American Numbering Plan (NANP) that has multiple area codes assigned. Overlay complexes are used to add central office prefixes in an NPA to increase the number of available telephone numbers.

• List of North American Numbering Plan area codes
• List of future North American area codes
• Original North American area codes
• Telephone numbers in the Americas