Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 925 [Rate centres in NPA 925] [Dial plan for NPA 925]

NXX: 684

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
925-684 A East Contra Costa CA BTISCA11RS0  9740 PACIFIC BELL 722      
925-684 0 East Contra Costa CA BTISCA11RS0  9740 PACIFIC BELL 722      
925-684 1 East Contra Costa CA BTISCA11RS0  9740 PACIFIC BELL 722      
925-684 2 East Contra Costa CA BTISCA11RS0  9740 PACIFIC BELL 722      
925-684 3 East Contra Costa CA BTISCA11RS0  9740 PACIFIC BELL 722      
925-684 4 East Contra Costa CA   394L COMCAST PHONE OF CALIFORNIA, LLC 722   2007-05-03   
925-684 5 East Contra Costa CA SNFCCAMKX1X  9262 UTILITY TELECOM GROUP, LLC - CA 722   2006-05-22   
925-684 6 East Contra Costa CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2013-03-29   
925-684 7 East Contra Costa CA   394L COMCAST PHONE OF CALIFORNIA, LLC 722   2010-05-10   
925-684 8 East Contra Costa CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2016-03-11   
925-684 9 East Contra Costa CA BTISCA11RS0  9740 PACIFIC BELL 722      

Last updated: Tue, 16 Jun 2026 00:09:45 UTC

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