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: 440

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
858-440 A La Mesa CA   6010 NEW CINGULAR WIRELESS PCS, LLC 732   2025-10-17   
858-440 9 La Mesa CA   6010 NEW CINGULAR WIRELESS PCS, LLC 732   2025-10-17   

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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