Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 310 [Rate centres in NPA 310] [Dial plan for NPA 310]

NXX: 510

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
310-510 A Avalon CA AVLNCA11RS0  9740 PACIFIC BELL 730      
310-510 0 Avalon CA AVLNCA11RS0  9740 PACIFIC BELL 730      
310-510 1 Avalon CA AVLNCA11RS0  9740 PACIFIC BELL 730      
310-510 2 Avalon CA AVLNCA11RS0  9740 PACIFIC BELL 730      
310-510 3 Avalon CA AVLNCA11RS0  9740 PACIFIC BELL 730      
310-510 4 Avalon CA AVLNCA11RS0  9740 PACIFIC BELL 730      
310-510 5 Avalon CA IRVNCASM1MD  671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 730   2011-04-22   
310-510 6 Avalon CA LSANCARCD3S  649C ONVOY, LLC - CA 730   2002-05-13   
310-510 7 Avalon CA AVLNCA11RS0  9740 PACIFIC BELL 730      
310-510 8 Avalon CA AVLNCA11RS0  9740 PACIFIC BELL 730      
310-510 9 Avalon CA AVLNCA11RS0  9740 PACIFIC BELL 730      

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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