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: 331

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-331 A Alden MI ALDNMIXHRS0  0695 FRONTIER NORTH, INC. - MI 348      
231-331 0 Alden MI   3535 ACD TELECOM, INC. - MI 348   2004-10-23   
231-331 1 Alden MI   543C ONVOY, LLCV - MI 348   2015-08-13   
231-331 2 Alden MI   543C ONVOY, LLCV - MI 348   2015-08-13   
231-331 3 Alden MI   991E BANDWIDTH.COM CLEC, LLC - MI 348   2012-04-13   
231-331 4 Alden MI   0695 FRONTIER NORTH, INC. - MI 348      
231-331 5 Alden MI   792K CHARTER IP ENABLED SERVICES, LLC 348   2007-02-25   
231-331 6 Alden MI   0695 FRONTIER NORTH, INC. - MI 348      
231-331 7 Alden MI   0695 FRONTIER NORTH, INC. - MI 348      
231-331 8 Alden MI   543C ONVOY, LLCV - MI 348   2013-04-01   
231-331 9 Alden MI   508J CENTURYLINK COMMUNICATIONS, LLC 348   2015-09-16   

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

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