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: 580

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
510-580 A Fremont-Newark: Oliver DA CA HYWRCA115MD  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 722      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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