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: 674

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-674 A Grant MI GDRPMIQLX5Y  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348      
231-674 0 Grant MI GDRPMIQLX5Y  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348      
231-674 1 Grant MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2012-12-30   
231-674 2 Grant MI GDRPMIBL15Z  516C AT&T CORP. 348   2011-01-31   
231-674 3 Grant MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2012-06-01   
231-674 4 Grant MI GDRPMIQLX5Y  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2004-07-17   
231-674 5 Grant MI GDRPMIBL00Z  991E BANDWIDTH.COM CLEC, LLC - MI 348   2014-09-01   
231-674 6 Grant MI TRCYMIMNWMD  508J CENTURYLINK COMMUNICATIONS, LLC 348   2015-09-15   
231-674 7 Grant MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2014-10-13   
231-674 8 Grant MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2016-03-21   
231-674 9 Grant MI GDRPMIQLX5Y  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348      

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

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