Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 670 [Rate centres in NPA 670] [Dial plan for NPA 670]

NXX: 488

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
670-488 A Tinian MP CHLONN01DS0  4974 GUAM WIRELESS TELEPHONE COMPANY, LLC 870      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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