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: 381

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-381 A White Cloud MI GFTPMIEF1MD  351D CHARTER FIBERLINK - MICHIGAN, LLC - MI 348      
231-381 0 White Cloud MI GFTPMIEF1MD  351D CHARTER FIBERLINK - MICHIGAN, LLC - MI 348   2021-06-27   
231-381 1 White Cloud MI   515J IP HORIZON LLC 348   2021-12-31   
231-381 3 White Cloud MI GDRPMIBL36Z  624H ONVOY SPECTRUM, LLC 348   2021-07-02   
231-381 7 White Cloud MI GDRPMIQLX5Y  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2023-03-09   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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