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: 328

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-328 A Johnson City TN JHCYTNXCXHY  318J COMCAST IP PHONE, LLC 956      
423-328 0 Johnson City TN JHCYTNXCXHY  318J COMCAST IP PHONE, LLC 956   2008-04-04   
423-328 1 Johnson City TN JHCYTNXC9MD  4806 LEVEL 3 COMMUNICATIONS, LLC - TN 956   2008-12-08   
423-328 2 Johnson City TN JHCYTNXCXYX  6214 NEW CINGULAR WIRELESS PCS, LLC - GA 956   2019-04-29   
423-328 3 Johnson City TN JHCYTNXCXHY  318J COMCAST IP PHONE, LLC 956   2013-05-13   
423-328 4 Johnson City TN JHCYTNXCX2Y  8645 SUNCOM DBA T-MOBILE USA 956   2009-03-26   
423-328 5 Johnson City TN JHCYTNXCXRX  114F TELEPORT COMMUNICATIONS AMERICA, LLC - TN 956   2011-06-20   
423-328 6 Johnson City TN JHCYTNXCX2Y  8645 SUNCOM DBA T-MOBILE USA 956   2010-03-30   
423-328 7 Johnson City TN JHCYTNXCXHY  318J COMCAST IP PHONE, LLC 956   2010-07-10   
423-328 8 Johnson City TN JHCYTNXC9MD  4806 LEVEL 3 COMMUNICATIONS, LLC - TN 956   2011-11-29   
423-328 9 Johnson City TN BUVLTNAXPS1  704C CHARTER FIBERLINK-TENNESSEE, LLC - TN 956   2014-05-12   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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