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: 321

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
510-321 A Oakland: Main-Piedmont DA CA SNFCCA21XEZ  6630 USA MOBILITY WIRELESS, INC. 722   2024-01-30   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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