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: 320

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-320 A Torch River Bridge MI GDRPMIBL00Z  991E BANDWIDTH.COM CLEC, LLC - MI 348      
231-320 0 Torch River Bridge MI   991E BANDWIDTH.COM CLEC, LLC - MI 348   2021-11-04   
231-320 1 Torch River Bridge MI   543C ONVOY, LLCV - MI 348   2023-08-06   
231-320 2 Torch River Bridge MI   543C ONVOY, LLCV - MI 348   2022-03-04   
231-320 4 Torch River Bridge MI   543C ONVOY, LLCV - MI 348   2023-01-04   
231-320 5 Torch River Bridge MI   145J TERRA NOVA TELECOM INC. 348   2025-07-12   
231-320 8 Torch River Bridge MI   543C ONVOY, LLCV - MI 348   2023-09-28   
231-320 9 Torch River Bridge MI   624H ONVOY SPECTRUM, LLC 348   2024-05-25   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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