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: 371

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-371 A Tustin MI GDRPMIBL00Z  991E BANDWIDTH.COM CLEC, LLC - MI 348      
231-371 0 Tustin MI GDRPMIBL00Z  991E BANDWIDTH.COM CLEC, LLC - MI 348   2021-11-06   
231-371 1 Tustin MI   145J TERRA NOVA TELECOM INC. 348   2024-02-14   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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