Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 231 [Rate centres in NPA 231] [Dial plan for NPA 231]

NXX:

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-923 A Hart MI   6664 SPRINT SPECTRUM L.P. 348      
231-923 0 Hart MI   6003 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 348   2013-10-02   
231-923 1 Hart MI   6003 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 348   2018-10-08   
231-923 2 Hart MI   6003 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 348   2014-07-07   
231-923 3 Hart MI   6003 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 348   2012-02-12   
231-923 4 Hart MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2004-07-17   
231-923 5 Hart MI   691A DAYSTARR, LLC DBA DAYSTARR COMMUNICATIONS - MI 348   2007-04-30   
231-923 6 Hart MI   6664 SPRINT SPECTRUM L.P. 348   2005-06-20   
231-923 7 Hart MI   770E TELEPORT COMMUNICATIONS AMERICA, LLC - MI 348   2013-08-06   
231-923 8 Hart MI   6003 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 348   2011-10-12   
231-923 9 Hart MI   6664 SPRINT SPECTRUM L.P. 348   2006-06-17   

Last updated: Thu, 10 Sep 2020 02:15:24 UTC

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