Area code 671

The area code 671 is the local telephone area code of the United States territory of Guam. It was created with the beginning of permissive dialing on July 1, 1997, replacing Guam's previous International Telecommunication Union country code 671, at the end of permissive dialing on July 1, 1998.

Prior to 1997, callers from the rest of the United States had to dial '011-671' and then the seven-digit telephone number to reach Guam, similar to international calls. As international calling rates began to fall in the more competitive destination countries during the 1990s, it became a considerable financial burden for people on the United States mainland to place calls to the United States territory of Guam, especially for those who were stationed in United States military bases there.

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