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: 412

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
858-412 A La Jolla CA   793K TWC IP ENABLED SERVICES, LLC 732      
858-412 0 La Jolla CA SNDACAGLDS2  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 732   2007-05-03   
858-412 1 La Jolla CA SNDGCAJWDS0  649C ONVOY, LLC - CA 732   2007-06-29   
858-412 2 La Jolla CA   8826 LEVEL 3 COMMUNICATIONS, LLC - CA 732   2007-05-04   
858-412 3 La Jolla CA   793K TWC IP ENABLED SERVICES, LLC 732   2007-07-12   
858-412 4 La Jolla CA   793K TWC IP ENABLED SERVICES, LLC 732   2007-01-10   
858-412 5 La Jolla CA   793K TWC IP ENABLED SERVICES, LLC 732   2007-01-10   
858-412 6 La Jolla CA   793K TWC IP ENABLED SERVICES, LLC 732   2007-07-12   
858-412 7 La Jolla CA SNDACAGLDS2  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 732   2007-07-20   
858-412 8 La Jolla CA   394L COMCAST PHONE OF CALIFORNIA, LLC 732   2008-08-09   
858-412 9 La Jolla CA ESCNCAKY2MD  6529 T-MOBILE USA, INC. 732   2007-09-28   

Last updated: Tue, 16 Jun 2026 00:09:45 UTC

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