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: 630

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-630 A Johnson City TN JHCYTNXCNMD  239E TELESCAN, INC. - TN 956      

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

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