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: 440

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
510-440 A Fremont-Newark: Oliver DA CA FRMTCA12DS0  9740 PACIFIC BELL 722      
510-440 0 Fremont-Newark: Oliver DA CA FRMTCA12DS0  9740 PACIFIC BELL 722      
510-440 1 Fremont-Newark: Oliver DA CA FRMTCA12DS0  9740 PACIFIC BELL 722      
510-440 3 Fremont-Newark: Oliver DA CA SNFCCA21XUY  981E BANDWIDTH.COM CLEC, LLC - CA 722   2021-01-08   
510-440 4 Fremont-Newark: Oliver DA CA FRMTCA12DS0  9740 PACIFIC BELL 722      
510-440 5 Fremont-Newark: Oliver DA CA SNJUCACLDS1  373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 722   2018-10-26   
510-440 6 Fremont-Newark: Oliver DA CA FRMTCA12DS0  9740 PACIFIC BELL 722      
510-440 7 Fremont-Newark: Oliver DA CA SNTDCAUJCM9  6010 NEW CINGULAR WIRELESS PCS, LLC 722   2022-12-17   
510-440 8 Fremont-Newark: Oliver DA CA FRMTCA12DS0  9740 PACIFIC BELL 722      
510-440 9 Fremont-Newark: Oliver DA CA FRMTCA12DS0  9740 PACIFIC BELL 722      

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

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