Local Calling Guide

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NPA: 661 [Rate centres in NPA 661] [Dial plan for NPA 661]

NXX: 600

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-600 A Santa Clarita: Newhall-Castaic DA CA LSANCA03DS3  7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 730      
661-600 0 Santa Clarita: Newhall-Castaic DA CA LSANCA03DS3  7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 730      
661-600 1 Santa Clarita: Newhall-Castaic DA CA LSANCA03DS3  7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 730      
661-600 2 Santa Clarita: Newhall-Castaic DA CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2005-01-03   
661-600 3 Santa Clarita: Newhall-Castaic DA CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2004-01-30   
661-600 4 Santa Clarita: Newhall-Castaic DA CA TRNECAGB7MD  899D METROPCS NETWORKS, LLC 730   2003-10-07   
661-600 5 Santa Clarita: Newhall-Castaic DA CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2005-02-03   
661-600 6 Santa Clarita: Newhall-Castaic DA CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2005-04-16   
661-600 7 Santa Clarita: Newhall-Castaic DA CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2005-06-10   
661-600 8 Santa Clarita: Newhall-Castaic DA CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2006-02-26   
661-600 9 Santa Clarita: Newhall-Castaic DA CA LSANCA54DS7  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 730   2013-03-02   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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