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: 599

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-599 A Eastport MI ESPTMIXGRS0  0695 FRONTIER NORTH, INC. - MI 348      
231-599 0 Eastport MI   3535 ACD TELECOM, INC. - MI 348   2004-10-22   
231-599 1 Eastport MI   792K CHARTER IP ENABLED SERVICES, LLC 348   2011-10-18   
231-599 2 Eastport MI   0695 FRONTIER NORTH, INC. - MI 348      
231-599 3 Eastport MI   0695 FRONTIER NORTH, INC. - MI 348      
231-599 4 Eastport MI   543C ONVOY, LLCV - MI 348   2015-12-09   
231-599 5 Eastport MI   543C ONVOY, LLCV - MI 348   2015-12-17   
231-599 6 Eastport MI   508J CENTURYLINK COMMUNICATIONS, LLC 348   2015-09-17   
231-599 7 Eastport MI   543C ONVOY, LLCV - MI 348   2013-04-01   
231-599 8 Eastport MI   543C ONVOY, LLCV - MI 348   2015-12-09   
231-599 9 Eastport MI   543C ONVOY, LLCV - MI 348   2015-12-17   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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