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: 790

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-790 A Freesoil MI GDRPMIBL52Z  829J PAETEC ITEL, LLC 348      
231-790 0 Freesoil MI   543C ONVOY, LLCV - MI 348   2016-03-24   
231-790 1 Freesoil MI   3535 ACD TELECOM, INC. - MI 348   2005-02-11   
231-790 2 Freesoil MI   543C ONVOY, LLCV - MI 348   2012-06-01   
231-790 3 Freesoil MI   543C ONVOY, LLCV - MI 348   2012-12-30   
231-790 4 Freesoil MI   543C ONVOY, LLCV - MI 348   2016-03-24   
231-790 5 Freesoil MI   516C AT&T CORP. 348   2011-08-23   
231-790 6 Freesoil MI   543C ONVOY, LLCV - MI 348   2013-04-01   
231-790 7 Freesoil MI   829J PAETEC ITEL, LLC 348   2004-02-03   
231-790 8 Freesoil MI   933G PEERLESS NETWORK OF MICHIGAN, LLC - MI 348   2015-12-26   
231-790 9 Freesoil MI   624H ONVOY SPECTRUM, LLC 348   2021-06-19   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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