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: 577

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-577 A Taft CA BKFDCA01X2X  5562 METROPCS, INC. 734      
661-577 0 Taft CA   624H ONVOY SPECTRUM, LLC 734   2021-12-08   
661-577 1 Taft CA   6529 T-MOBILE USA, INC. 734   2015-03-09   
661-577 2 Taft CA   5562 METROPCS, INC. 734      
661-577 3 Taft CA   6529 T-MOBILE USA, INC. 734   2015-03-09   
661-577 4 Taft CA   8826 LEVEL 3 COMMUNICATIONS, LLC - CA 734   2005-07-30   
661-577 5 Taft CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 734   2017-05-26   
661-577 6 Taft CA   5562 METROPCS, INC. 734      
661-577 7 Taft CA   5562 METROPCS, INC. 734      
661-577 8 Taft CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 734   2022-05-26   
661-577 9 Taft CA   649C ONVOY, LLC - CA 734   2021-07-22   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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