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: 557

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
323-557 A Los Angeles: DA 13 CA ONTRCAFXDS0  7718 LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 730      
323-557 0 Los Angeles: DA 13 CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2006-10-13   
323-557 1 Los Angeles: DA 13 CA ONTRCAFXDS0  7718 LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 730      
323-557 2 Los Angeles: DA 13 CA TRNECAGB7MD  899D METROPCS NETWORKS, LLC 730   2007-06-23   
323-557 3 Los Angeles: DA 13 CA TRNECAGB7MD  899D METROPCS NETWORKS, LLC 730   2007-06-23   
323-557 4 Los Angeles: DA 13 CA TRNECAGB7MD  899D METROPCS NETWORKS, LLC 730   2008-11-13   
323-557 5 Los Angeles: DA 13 CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2007-06-15   
323-557 6 Los Angeles: DA 13 CA TRNECAGB7MD  899D METROPCS NETWORKS, LLC 730   2007-06-23   
323-557 7 Los Angeles: DA 13 CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2007-04-21   
323-557 8 Los Angeles: DA 13 CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2007-01-02   
323-557 9 Los Angeles: DA 13 CA TRNECAGB7MD  899D METROPCS NETWORKS, LLC 730   2008-11-13   

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

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