Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 408 [Rate centres in NPA 408] [Dial plan for NPA 408]

NXX: 431

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
408-431 A Sunnyvale CA SNTDCAUJCM9  6010 NEW CINGULAR WIRELESS PCS, LLC 722      

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

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