Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 661 [Rate centres in NPA 661] [Dial plan for NPA 661]

NXX: 674

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-674 A Lancaster CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730      
661-674 0 Lancaster CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2011-05-08   
661-674 1 Lancaster CA   515J IP HORIZON LLC 730      
661-674 2 Lancaster CA   515J IP HORIZON LLC 730      
661-674 3 Lancaster CA ONTRCAFXDS0  7718 LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 730   2010-08-18   
661-674 4 Lancaster CA   515J IP HORIZON LLC 730      
661-674 5 Lancaster CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2004-06-02   
661-674 6 Lancaster CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2003-12-14   
661-674 7 Lancaster CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2003-04-05   
661-674 8 Lancaster CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2004-04-21   
661-674 9 Lancaster CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2003-04-05   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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