Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

NPA: 623 [Rate centres in NPA 623] [Dial plan for NPA 623]

NXX: 955

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-955 A Phoenix AZ PHNXAZMAXGZ  907K ALLO COMMUNICATIONS LLC 666   2025-12-19   
623-955 0 Phoenix AZ PHNZAZZJAMD  6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 666   2025-12-22   
623-955 1 Phoenix AZ PHNZAZZJAMD  6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 666   2025-12-22   
623-955 2 Phoenix AZ PHNXAZ19DMD  490J BOOST SUBSCRIBERCO L.L.C. 666   2026-02-02   
623-955 3 Phoenix AZ PHNXAZ19DMD  490J BOOST SUBSCRIBERCO L.L.C. 666   2026-02-23   
623-955 4 Phoenix AZ PHNXAZ19DMD  490J BOOST SUBSCRIBERCO L.L.C. 666   2026-03-16   
623-955 5 Phoenix AZ PHNXAZMAXGZ  907K ALLO COMMUNICATIONS LLC 666   2025-12-19   
623-955 6 Phoenix AZ PHNXAZ19DMD  490J BOOST SUBSCRIBERCO L.L.C. 666   2026-04-06   
623-955 7 Phoenix AZ PHNXAZ19DMD  490J BOOST SUBSCRIBERCO L.L.C. 666   2026-04-27   
623-955 8 Phoenix AZ PHNZAZZJAMD  6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 666   2025-12-22   
623-955 9 Phoenix AZ PHNZAZZJAMD  6572 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - AZ 666   2025-12-22   

Last updated: Thu, 16 Jul 2026 02:21:55 UTC

Sponsored by: Callcentric - VoIP Internet phone service

Like this site? We accept donations via PayPal.