Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 424 [Rate centres in NPA 424] [Dial plan for NPA 424]

NXX: 557

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
424-557 A El Segundo CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2025-09-11   
424-557 0 El Segundo CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2025-09-11   
424-557 1 El Segundo CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2025-09-11   
424-557 7 El Segundo CA   145J TERRA NOVA TELECOM INC. 730   2025-09-12   
424-557 8 El Segundo CA   649C ONVOY, LLC - CA 730   2025-10-12   

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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