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]

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NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-994 5 Lake Leelanau MI   516C AT&T CORP. 348   2011-08-23   
231-994 6 Lake Leelanau MI   543C ONVOY, LLCV - MI 348   2012-06-01   
231-994 7 Lake Leelanau MI   3535 ACD TELECOM, INC. - MI 348   2005-03-12   
231-994 8 Lake Leelanau MI   543C ONVOY, LLCV - MI 348   2013-01-03   
231-994 9 Lake Leelanau MI   543C ONVOY, LLCV - MI 348   2013-03-18   
231-995 A Traverse City MI TRCYMIMNDS1  9323 MICHIGAN BELL TEL CO 348      
231-999 A Central Lake MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348      
231-999 1 Central Lake MI   991E BANDWIDTH.COM CLEC, LLC - MI 348   2021-08-21   
231-999 2 Central Lake MI   543C ONVOY, LLCV - MI 348   2021-03-06   
231-999 3 Central Lake MI   543C ONVOY, LLCV - MI 348   2021-03-06   
231-999 4 Central Lake MI   145J TERRA NOVA TELECOM INC. 348   2025-07-12   
231-999 5 Central Lake MI   624H ONVOY SPECTRUM, LLC 348   2021-06-18   
231-999 7 Central Lake MI   508J CENTURYLINK COMMUNICATIONS, LLC 348   2015-10-21   
231-999 8 Central Lake MI   543C ONVOY, LLCV - MI 348   2015-10-19   
231-999 9 Central Lake MI   543C ONVOY, LLCV - MI 348   2015-10-19   

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

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