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: 622

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-622 A Phoenix AZ   490J BOOST SUBSCRIBERCO L.L.C. 666   2026-12-03   
623-622 6 Phoenix AZ   490J BOOST SUBSCRIBERCO L.L.C. 666   2026-12-03   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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