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: 357

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
510-357 A Oakland: Trinidad DA CA SNLNCA11DS0  9740 PACIFIC BELL 722      

Last updated: Wed, 04 Mar 2026 03:00:52 UTC

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