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: 920

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-920 A Phoenix AZ PHNXAZ28DS3  630E ONVOY, LLC - AZ 666      
623-920 0 Phoenix AZ   630E ONVOY, LLC - AZ 666   2021-04-02   
623-920 1 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2021-04-17   
623-920 2 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2021-04-17   
623-920 3 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2021-04-03   
623-920 4 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2021-04-03   
623-920 5 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2021-04-03   
623-920 6 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2021-04-03   
623-920 7 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2021-04-03   
623-920 8 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2021-04-03   
623-920 9 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2021-04-03   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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