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: 256

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
858-256 A San Diego: Linda Vista DA CA   394L COMCAST PHONE OF CALIFORNIA, LLC 732      
858-256 0 San Diego: Linda Vista DA CA   793K TWC IP ENABLED SERVICES, LLC 732   2013-07-11   
858-256 1 San Diego: Linda Vista DA CA SNDGCAJWDS0  649C ONVOY, LLC - CA 732   2013-06-19   
858-256 2 San Diego: Linda Vista DA CA   394L COMCAST PHONE OF CALIFORNIA, LLC 732   2013-05-01   
858-256 3 San Diego: Linda Vista DA CA SNDKCA882MD  671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 732   2013-06-03   
858-256 4 San Diego: Linda Vista DA CA SNDGCA02XIZ  981E BANDWIDTH.COM CLEC, LLC - CA 732   2013-05-03   
858-256 5 San Diego: Linda Vista DA CA SNDGCA02XIZ  981E BANDWIDTH.COM CLEC, LLC - CA 732   2013-05-03   
858-256 6 San Diego: Linda Vista DA CA SNDGCA02XIZ  981E BANDWIDTH.COM CLEC, LLC - CA 732   2013-05-03   
858-256 7 San Diego: Linda Vista DA CA SNDACAGLDS2  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 732   2013-06-21   
858-256 8 San Diego: Linda Vista DA CA SNDGCAJWDS0  649C ONVOY, LLC - CA 732   2013-06-19   
858-256 9 San Diego: Linda Vista DA CA   793K TWC IP ENABLED SERVICES, LLC 732   2013-09-01   

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

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