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: 421

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
858-421 A Rancho Bernardo CA SNDGCA51CM3  6010 NEW CINGULAR WIRELESS PCS, LLC 732   2025-03-10   
858-421 0 Rancho Bernardo CA SNDGCAJWDS0  649C ONVOY, LLC - CA 732   2026-06-25   
858-421 6 Rancho Bernardo CA   7147 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 732   2026-08-17   
858-421 8 Rancho Bernardo CA SNDGCA51CM3  6010 NEW CINGULAR WIRELESS PCS, LLC 732   2025-03-10   
858-421 9 Rancho Bernardo CA SNDGCA51CM3  6010 NEW CINGULAR WIRELESS PCS, LLC 732   2025-03-10   

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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