Local Calling Guide

Area code/prefix search

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Fremont-Newark: Oliver DA, CA

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
510-623 4 OKLDCA03DS5  7145 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 722   2015-07-01   
510-623 5 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-623 6 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-623 7 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-623 8 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-623 9 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-624 A FRMTCA12DS0  9740 PACIFIC BELL 722      
510-624 0 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-624 1 SNJUCACLDS1  373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 722   2022-12-10   
510-624 2 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-624 3 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-624 4 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-624 5 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-624 6 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-624 7 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-624 8 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-624 9 OKLDCA03XOY  318J COMCAST IP PHONE, LLC 722   2015-04-24   
510-651 A FRMTCA12DS0  9740 PACIFIC BELL 722      
510-656 A FRMTCA12DS0  9740 PACIFIC BELL 722      
510-657 A FRMTCA12DS0  9740 PACIFIC BELL 722      
510-659 A FRMTCA12DS0  9740 PACIFIC BELL 722      
510-659 0 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-659 1 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-659 2 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-659 3 SNFCCAMKX1X  9262 UTILITY TELECOM GROUP, LLC - CA 722      
510-659 4 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-659 5 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-659 6 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-659 7 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-659 8 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-659 9 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-661 A FRMTCA12DS0  9740 PACIFIC BELL 722      
510-661 0 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-661 1 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-661 2 SNTDCAUJCM9  6010 NEW CINGULAR WIRELESS PCS, LLC 722   2021-12-11   
510-661 3 SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2014-09-25   
510-661 4 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-661 5 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-661 6 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-661 7 SNFCCAMKX1X  9262 UTILITY TELECOM GROUP, LLC - CA 722      
510-661 8 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-661 9 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-668 A FRMTCA12DS0  9740 PACIFIC BELL 722      
510-668 0 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-668 1 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-668 2 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-668 3 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-668 4 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-668 5 FRMTCA12DS0  9740 PACIFIC BELL 722      
510-668 6 FRMTCA12DS0  9740 PACIFIC BELL 722      

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Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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