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: 779

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-779 A Arvin CA BKFDCA12DS1  7718 LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 734      
661-779 0 Arvin CA   6529 T-MOBILE USA, INC. 734   2015-04-23   
661-779 1 Arvin CA   7718 LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 734      
661-779 2 Arvin CA   6529 T-MOBILE USA, INC. 734   2015-04-23   
661-779 3 Arvin CA   6529 T-MOBILE USA, INC. 734   2015-04-23   
661-779 4 Arvin CA   6529 T-MOBILE USA, INC. 734   2016-09-06   
661-779 5 Arvin CA   6529 T-MOBILE USA, INC. 734   2015-04-23   
661-779 6 Arvin CA   981E BANDWIDTH.COM CLEC, LLC - CA 734   2015-11-15   
661-779 7 Arvin CA   508J CENTURYLINK COMMUNICATIONS, LLC 734   2015-05-05   
661-779 8 Arvin CA   6529 T-MOBILE USA, INC. 734   2015-04-23   
661-779 9 Arvin CA   6529 T-MOBILE USA, INC. 734   2015-04-23   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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