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: 678

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-678 A Brethren MI GDRPMIBLXTZ  3535 ACD TELECOM, INC. - MI 348      
231-678 7 Brethren MI   3535 ACD TELECOM, INC. - MI 348   2005-03-12   
231-678 8 Brethren MI   145J TERRA NOVA TELECOM INC. 348   2025-06-05   

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

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