Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 623 [Rate centres in NPA 623] [Dial plan for NPA 623]

NXX: 815

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-815 A Phoenix AZ PHNXAZMRDS0  9636 QWEST CORPORATION 666      

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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