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: 774

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-774 A Interlochen MI GDRPMIBLXTZ  3535 ACD TELECOM, INC. - MI 348      
231-774 0 Interlochen MI   817J INTERACTIVE SERVICES NETWORK, INC. 348   2005-09-02   
231-774 2 Interlochen MI   543C ONVOY, LLCV - MI 348   2012-06-01   
231-774 3 Interlochen MI   543C ONVOY, LLCV - MI 348   2012-12-30   
231-774 4 Interlochen MI   543C ONVOY, LLCV - MI 348   2013-03-18   
231-774 5 Interlochen MI   516C AT&T CORP. 348   2011-08-23   
231-774 6 Interlochen MI   991E BANDWIDTH.COM CLEC, LLC - MI 348   2014-12-26   
231-774 7 Interlochen MI   3535 ACD TELECOM, INC. - MI 348   2005-03-12   
231-774 8 Interlochen MI   543C ONVOY, LLCV - MI 348   2016-03-23   
231-774 9 Interlochen MI   933G PEERLESS NETWORK OF MICHIGAN, LLC - MI 348   2015-12-22   

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

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