Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 510 [Rate centres in NPA 510] [Dial plan for NPA 510]

NXX: 279

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
510-279 A Fremont-Newark: Oliver DA CA SNFCCASY5MD  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 722      
510-279 0 Fremont-Newark: Oliver DA CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722      
510-279 1 Fremont-Newark: Oliver DA CA SNFCCASY5MD  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 722      
510-279 2 Fremont-Newark: Oliver DA CA SNJSCAYB0MD  671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 722      
510-279 3 Fremont-Newark: Oliver DA CA SNFCCASY5MD  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 722   2005-01-07   
510-279 4 Fremont-Newark: Oliver DA CA SNFCCASY5MD  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 722   2003-03-04   
510-279 5 Fremont-Newark: Oliver DA CA SNJSCAYB0MD  671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 722      
510-279 6 Fremont-Newark: Oliver DA CA SNFCCA21XUY  981E BANDWIDTH.COM CLEC, LLC - CA 722   2021-01-08   
510-279 7 Fremont-Newark: Oliver DA CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722      
510-279 8 Fremont-Newark: Oliver DA CA SNFCCA21XUY  981E BANDWIDTH.COM CLEC, LLC - CA 722   2011-06-23   
510-279 9 Fremont-Newark: Oliver DA CA SNTDCAUJCM9  6010 NEW CINGULAR WIRELESS PCS, LLC 722   2024-08-26   

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

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