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: 439

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
858-439 A Chula Vista CA   6010 NEW CINGULAR WIRELESS PCS, LLC 732   2025-08-08   
858-439 0 Chula Vista CA   649C ONVOY, LLC - CA 732   2025-10-26   
858-439 7 Chula Vista CA   6010 NEW CINGULAR WIRELESS PCS, LLC 732   2025-08-08   
858-439 8 Chula Vista CA   6010 NEW CINGULAR WIRELESS PCS, LLC 732   2025-08-08   
858-439 9 Chula Vista CA   6010 NEW CINGULAR WIRELESS PCS, LLC 732   2025-08-08   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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