Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 323 [Rate centres in NPA 323] [Dial plan for NPA 323]

NXX: 203

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
323-203 A Los Angeles: DA 14 CA LSANCA03DS3  7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 730      
323-203 0 Los Angeles: DA 14 CA LSANCA54DS7  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 730   2005-12-11   
323-203 1 Los Angeles: DA 14 CA LSANCA54DS7  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 730   2005-12-11   
323-203 2 Los Angeles: DA 14 CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2006-02-03   
323-203 3 Los Angeles: DA 14 CA LSANCA03DS3  7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 730      
323-203 4 Los Angeles: DA 14 CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2006-02-03   
323-203 5 Los Angeles: DA 14 CA CYCMCALLCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 730   2003-12-15   
323-203 6 Los Angeles: DA 14 CA CYCMCALLCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 730   2003-01-28   
323-203 7 Los Angeles: DA 14 CA CYCMCALLCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 730   2003-01-28   
323-203 8 Los Angeles: DA 14 CA CYCMCALLCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 730   2003-08-26   
323-203 9 Los Angeles: DA 14 CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2007-10-24   

Last updated: Sun, 27 Apr 2025 12:48:38 UTC

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