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: 319

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
858-319 A La Jolla CA ESCNCAKY2MD  6529 T-MOBILE USA, INC. 732      
858-319 1 La Jolla CA   624H ONVOY SPECTRUM, LLC 732   2021-05-23   
858-319 2 La Jolla CA   7147 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 732   2021-05-16   
858-319 3 La Jolla CA   7147 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 732   2021-05-16   
858-319 4 La Jolla CA   7147 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 732   2021-05-16   
858-319 5 La Jolla CA   6529 T-MOBILE USA, INC. 732   2021-05-15   
858-319 6 La Jolla CA   6529 T-MOBILE USA, INC. 732   2021-05-15   
858-319 7 La Jolla CA   6529 T-MOBILE USA, INC. 732   2021-05-15   
858-319 8 La Jolla CA   6529 T-MOBILE USA, INC. 732   2021-05-15   
858-319 9 La Jolla CA   6529 T-MOBILE USA, INC. 732   2021-05-15   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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