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: 540

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-540 A Palmdale: Palmdale DA CA PLDLCA01DS0  9740 PACIFIC BELL 730      
661-540 0 Palmdale: Palmdale DA CA   9740 PACIFIC BELL 730      
661-540 1 Palmdale: Palmdale DA CA   9740 PACIFIC BELL 730      
661-540 2 Palmdale: Palmdale DA CA   9740 PACIFIC BELL 730      
661-540 3 Palmdale: Palmdale DA CA   899D METROPCS NETWORKS, LLC 730   2011-04-02   
661-540 4 Palmdale: Palmdale DA CA   9740 PACIFIC BELL 730      
661-540 5 Palmdale: Palmdale DA CA   9262 UTILITY TELECOM GROUP, LLC - CA 730      
661-540 6 Palmdale: Palmdale DA CA   9740 PACIFIC BELL 730      
661-540 7 Palmdale: Palmdale DA CA   9740 PACIFIC BELL 730      
661-540 8 Palmdale: Palmdale DA CA   9740 PACIFIC BELL 730      
661-540 9 Palmdale: Palmdale DA CA   9740 PACIFIC BELL 730      

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

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