Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 423 [Rate centres in NPA 423] [Dial plan for NPA 423]

NXX: 412

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-412 A Johnson City TN JHCYTNXCXNX  6630 USA MOBILITY WIRELESS, INC. 956      

Last updated: Fri, 25 Jul 2025 03:21:23 UTC

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