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: 644

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
408-644 A San Jose: South DA CA OKLECAZV1MD  6529 T-MOBILE USA, INC. 722      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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