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: 559

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
925-559 A East Contra Costa CA CNCRCADOCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 722   2026-03-06   
925-559 7 East Contra Costa CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2026-06-14   
925-559 8 East Contra Costa CA SNFCCAMKDS3  649C ONVOY, LLC - CA 722   2026-06-14   
925-559 9 East Contra Costa CA CNCRCADOCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 722   2026-03-06   

Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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