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: 728

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-728 A Lancaster CA LNCSCAXG94K  2319 FRONTIER CALIFORNIA INC. 730      
661-728 0 Lancaster CA   2319 FRONTIER CALIFORNIA INC. 730      
661-728 1 Lancaster CA   981E BANDWIDTH.COM CLEC, LLC - CA 730   2011-05-27   
661-728 2 Lancaster CA   2319 FRONTIER CALIFORNIA INC. 730      
661-728 3 Lancaster CA   2319 FRONTIER CALIFORNIA INC. 730      
661-728 4 Lancaster CA   2319 FRONTIER CALIFORNIA INC. 730      
661-728 5 Lancaster CA   9262 UTILITY TELECOM GROUP, LLC - CA 730   2006-06-21   
661-728 6 Lancaster CA   6529 T-MOBILE USA, INC. 730   2007-09-28   
661-728 7 Lancaster CA   6529 T-MOBILE USA, INC. 730   2007-09-28   
661-728 8 Lancaster CA   6529 T-MOBILE USA, INC. 730   2007-09-28   
661-728 9 Lancaster CA   2319 FRONTIER CALIFORNIA INC. 730      

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

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