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: 983

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
408-983 A San Jose: West DA CA SNTCCA11DS1  9740 PACIFIC BELL 722      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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