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: 923

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-923 A Hart MI GDRPMIBLXDZ  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348      
231-923 0 Hart MI GDRQMIBODMD  6003 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 348   2013-10-02   
231-923 1 Hart MI GDRQMIBODMD  6003 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 348   2018-10-08   
231-923 2 Hart MI GDRQMIBODMD  6003 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 348   2014-07-07   
231-923 3 Hart MI GDRQMIBODMD  6003 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 348   2012-02-12   
231-923 4 Hart MI GDRPMIQLX5Y  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2004-07-17   
231-923 5 Hart MI MSKGMIXKFMD  691A DAYSTARR, LLC DBA DAYSTARR COMMUNICATIONS - MI 348   2007-04-30   
231-923 6 Hart MI GDRPMIBLXDZ  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2005-06-20   
231-923 7 Hart MI GDRPMIBL06Z  770E TELEPORT COMMUNICATIONS AMERICA, LLC - MI 348   2013-08-06   
231-923 8 Hart MI GDRQMIBODMD  6003 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 348   2011-10-12   
231-923 9 Hart MI GDRPMIBLXDZ  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2006-06-17   

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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