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: 373

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-373 A Phoenix AZ   597F VOIP INNOVATIONS, LLC 666   2026-06-13   
623-373 0 Phoenix AZ   597F VOIP INNOVATIONS, LLC 666   2026-06-13   

Last updated: Sat, 02 May 2026 12:20:53 UTC

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