Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 858 [Rate centres in NPA 858] [Dial plan for NPA 858]

NXX: 423

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
858-423 A San Diego: San Diego DA CA SNDICAETAMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 732   2025-03-30   
858-423 0 San Diego: San Diego DA CA SNDICAETAMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 732   2025-03-30   
858-423 1 San Diego: San Diego DA CA SNDICAETAMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 732   2025-03-30   
858-423 3 San Diego: San Diego DA CA   6010 NEW CINGULAR WIRELESS PCS, LLC 732   2026-08-13   
858-423 4 San Diego: San Diego DA CA SNDGCA0260Z  624H ONVOY SPECTRUM, LLC 732   2025-03-31   
858-423 5 San Diego: San Diego DA CA SNDGCA0260Z  624H ONVOY SPECTRUM, LLC 732   2025-03-31   
858-423 6 San Diego: San Diego DA CA SNDICAETAMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 732   2026-03-14   
858-423 7 San Diego: San Diego DA CA SNDGCA0260Z  624H ONVOY SPECTRUM, LLC 732   2025-03-31   
858-423 8 San Diego: San Diego DA CA SNDGCA0260Z  624H ONVOY SPECTRUM, LLC 732   2025-03-31   

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

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