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   6010 NEW CINGULAR WIRELESS PCS, LLC 732   2025-03-10   
858-421 8 Rancho Bernardo CA   6010 NEW CINGULAR WIRELESS PCS, LLC 732   2025-03-10   
858-421 9 Rancho Bernardo CA   6010 NEW CINGULAR WIRELESS PCS, LLC 732   2025-03-10   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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