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: 257

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
510-257 A Fremont-Newark: Oliver DA CA SNJSCA02DS4  7145 TELEPORT COMMUNICATIONS GROUP - SAN FRANCISCO 722      
510-257 0 Fremont-Newark: Oliver DA CA SNJSCA02DS4  7145 TELEPORT COMMUNICATIONS GROUP - SAN FRANCISCO 722      
510-257 1 Fremont-Newark: Oliver DA CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2007-09-07   
510-257 2 Fremont-Newark: Oliver DA CA SNFCCAMMDSA  4129 O1 COMMUNICATIONS, INC. - CA 722   2003-10-12   
510-257 3 Fremont-Newark: Oliver DA CA SNFCCAMMDSA  4129 O1 COMMUNICATIONS, INC. - CA 722   2003-10-12   
510-257 4 Fremont-Newark: Oliver DA CA SNFCCASY5MD  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 722   2004-11-29   
510-257 5 Fremont-Newark: Oliver DA CA FRMTCAEDDS2  7262 XO CALIFORNIA, INC. 722   2005-09-15   
510-257 6 Fremont-Newark: Oliver DA CA FRMTCAEDDS2  7262 XO CALIFORNIA, INC. 722   2005-09-15   
510-257 7 Fremont-Newark: Oliver DA CA FRMTCAEDDS0  7262 XO CALIFORNIA, INC. 722   2005-09-15   
510-257 8 Fremont-Newark: Oliver DA CA FRMTCAEDDS0  7262 XO CALIFORNIA, INC. 722   2005-09-15   
510-257 9 Fremont-Newark: Oliver DA CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2014-09-25   

Last updated: Sun, 07 Feb 2021 01:52:50 UTC

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