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: 266

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-266 A Irons MI IRONMIIRRS1  9323 MICHIGAN BELL TEL CO 348      
231-266 0 Irons MI   543C ONVOY, LLCV - MI 348   2015-08-02   
231-266 1 Irons MI   3535 ACD TELECOM, INC. - MI 348   2005-02-11   
231-266 2 Irons MI   9323 MICHIGAN BELL TEL CO 348      
231-266 3 Irons MI   543C ONVOY, LLCV - MI 348   2013-03-18   
231-266 4 Irons MI   543C ONVOY, LLCV - MI 348   2016-04-14   
231-266 5 Irons MI   9323 MICHIGAN BELL TEL CO 348      
231-266 6 Irons MI   543C ONVOY, LLCV - MI 348   2016-04-14   
231-266 7 Irons MI   933G PEERLESS NETWORK OF MICHIGAN, LLC - MI 348   2019-09-13   
231-266 8 Irons MI   9323 MICHIGAN BELL TEL CO 348      
231-266 9 Irons 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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