Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 520 [Rate centres in NPA 520] [Dial plan for NPA 520]

NXX: 378

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
520-378 A Sierra Vista AZ SRVSAZSODS0  9636 QWEST CORPORATION 668      

Last updated: Wed, 07 Feb 2024 04:12:25 UTC

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