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: 243

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
510-243 A El Sobrante-Pinole CA ELSBCA11DS0  9740 PACIFIC BELL 722      
510-243 0 El Sobrante-Pinole CA   9740 PACIFIC BELL 722      
510-243 1 El Sobrante-Pinole CA   9740 PACIFIC BELL 722      
510-243 2 El Sobrante-Pinole CA   9740 PACIFIC BELL 722      
510-243 3 El Sobrante-Pinole CA   9740 PACIFIC BELL 722      
510-243 4 El Sobrante-Pinole CA   9740 PACIFIC BELL 722   2002-05-08   
510-243 5 El Sobrante-Pinole CA   318J COMCAST IP PHONE, LLC 722   2011-09-29   
510-243 6 El Sobrante-Pinole CA   9740 PACIFIC BELL 722      
510-243 7 El Sobrante-Pinole CA   9740 PACIFIC BELL 722      
510-243 8 El Sobrante-Pinole CA   9740 PACIFIC BELL 722      
510-243 9 El Sobrante-Pinole CA   9740 PACIFIC BELL 722      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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