Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 424 [Rate centres in NPA 424] [Dial plan for NPA 424]

NXX: 558

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
424-558 A Torrance CA CYCMCALLCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 730      
424-558 0 Torrance CA CYCMCALLCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 730   2006-08-26   
424-558 1 Torrance CA CYCMCALLCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 730   2006-08-26   
424-558 2 Torrance CA CYCMCALLCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 730   2007-05-19   
424-558 3 Torrance CA ANHMCA01XEY  516C AT&T CORP. 730   2006-08-28   
424-558 4 Torrance CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2007-09-02   
424-558 5 Torrance CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2016-10-08   
424-558 6 Torrance CA CYCMCALLCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 730   2007-10-21   
424-558 7 Torrance CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2007-11-03   
424-558 8 Torrance CA   793K TWC IP ENABLED SERVICES, LLC 730   2007-01-10   
424-558 9 Torrance CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2006-10-26   

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

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