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: 597

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-597 A Cheboygan MI CHBYMIMNRSA  9323 MICHIGAN BELL TEL CO 348      
231-597 0 Cheboygan MI   9323 MICHIGAN BELL TEL CO 348      
231-597 1 Cheboygan MI   9323 MICHIGAN BELL TEL CO 348      
231-597 2 Cheboygan MI   9323 MICHIGAN BELL TEL CO 348      
231-597 3 Cheboygan MI   7157 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI 348   2010-09-01   
231-597 4 Cheboygan MI   543C ONVOY, LLCV - MI 348   2012-12-29   
231-597 5 Cheboygan MI   543C ONVOY, LLCV - MI 348   2013-04-01   
231-597 6 Cheboygan MI   991E BANDWIDTH.COM CLEC, LLC - MI 348   2016-08-26   
231-597 7 Cheboygan MI   543C ONVOY, LLCV - MI 348   2012-06-01   
231-597 8 Cheboygan MI   9323 MICHIGAN BELL TEL CO 348      
231-597 9 Cheboygan MI   9323 MICHIGAN BELL TEL CO 348      

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

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