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: 974

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-974 A Lancaster CA NHLLCA01DS0  7480 PACIFIC BELL (COMPETITIVE) 730      
661-974 0 Lancaster CA   6529 T-MOBILE USA, INC. 730   2007-07-24   
661-974 1 Lancaster CA   6529 T-MOBILE USA, INC. 730   2007-05-25   
661-974 2 Lancaster CA   6529 T-MOBILE USA, INC. 730   2007-05-25   
661-974 3 Lancaster CA   6529 T-MOBILE USA, INC. 730   2007-05-25   
661-974 4 Lancaster CA   6529 T-MOBILE USA, INC. 730   2007-07-24   
661-974 5 Lancaster CA   6529 T-MOBILE USA, INC. 730   2007-07-24   
661-974 6 Lancaster CA   6529 T-MOBILE USA, INC. 730   2007-07-24   
661-974 7 Lancaster CA   7480 PACIFIC BELL (COMPETITIVE) 730      
661-974 8 Lancaster CA   7480 PACIFIC BELL (COMPETITIVE) 730   2004-10-16   
661-974 9 Lancaster CA   6529 T-MOBILE USA, INC. 730   2007-07-24   

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

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