Local Calling Guide

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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 AMERICA, LLC - CA 722      
510-257 0 Fremont-Newark: Oliver DA CA SNJSCA02DS4  7145 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 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   515J IP HORIZON LLC 722   2003-10-12   
510-257 3 Fremont-Newark: Oliver DA CA   515J IP HORIZON LLC 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 HYWRCA115MD  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 722   2005-09-15   
510-257 6 Fremont-Newark: Oliver DA CA HYWRCA115MD  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 722   2005-09-15   
510-257 7 Fremont-Newark: Oliver DA CA HYWRCA115MD  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 722   2005-09-15   
510-257 8 Fremont-Newark: Oliver DA CA HYWRCA115MD  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 722   2005-09-15   
510-257 9 Fremont-Newark: Oliver DA CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2014-09-25   

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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