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: 289

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-289 A Morristown TN KNVLTNMA96Z  7476 POWERTEL NASHVILLE LICENSES, INC. 474      
423-289 0 Morristown TN KNVLTNMAYAY  829J PAETEC ITEL, LLC 474   2004-03-27   
423-289 1 Morristown TN KNVLTNMAYAY  829J PAETEC ITEL, LLC 474   2010-04-23   
423-289 2 Morristown TN KNVLTNMA96Z  7476 POWERTEL NASHVILLE LICENSES, INC. 474   2011-03-13   
423-289 3 Morristown TN KNVLTNMA49Z  525E ONVOY, LLC - TN 474   2008-06-10   
423-289 4 Morristown TN KNVLTNMA49Z  525E ONVOY, LLC - TN 474   2008-06-16   
423-289 5 Morristown TN KNVNTNEC5MD  145J TERRA NOVA TELECOM INC. 474   2024-12-29   
423-289 7 Morristown TN   145J TERRA NOVA TELECOM INC. 474   2026-07-05   
423-289 8 Morristown TN   145J TERRA NOVA TELECOM INC. 474   2025-10-04   

Last updated: Fri, 10 Jul 2026 02:55:48 UTC

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