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: 600

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
858-600 A San Diego: San Diego DA CA   114J EXIANT COMMUNICATIONS LLC 732   2026-05-01   
858-600 0 San Diego: San Diego DA CA   114J EXIANT COMMUNICATIONS LLC 732   2026-05-01   

Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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