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: 800

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-800 A Luther MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348      
231-800 0 Luther MI   543C ONVOY, LLCV - MI 348   2017-11-26   
231-800 2 Luther MI   624H ONVOY SPECTRUM, LLC 348   2021-06-19   
231-800 5 Luther MI   792K CHARTER IP ENABLED SERVICES, LLC 348   2023-07-05   
231-800 7 Luther MI   516C AT&T CORP. 348   2023-09-25   
231-800 8 Luther MI   543C ONVOY, LLCV - MI 348   2017-11-26   

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

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