The 671 area code serves a unique and specific purpose within the North American Numbering Plan (NANP), distinct from the typical geographic area codes assigned within the United States and Canada.

Assigned to Guam: The 671 area code is designated for Guam, a U.S. territory located in the Western Pacific Ocean. This area code is not associated with a location within the continental United States but is part of the NANP, which includes several territories and countries in North America and the Caribbean.

International Dialing Considerations: Calls to the 671 area code from within the United States or Canada are treated as domestic calls, not international. This is because Guam is a U.S. territory and part of the NANP. Callers should dial the area code and the local number, without needing to use an international access code.

Supporting Communication in Guam: The 671 area code facilitates connectivity for the residents and businesses of Guam, as well as for tourists and other visitors. It ensures effective communication within the territory and with the mainland United States and other NANP member areas.

The 671 area code represents Guam's integration into the North American telecommunications system, facilitating connectivity for this Pacific territory with the rest of the NANP region.