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: 277

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-277 A Fountain MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348      
231-277 0 Fountain MI   543C ONVOY, LLCV - MI 348   2016-05-20   
231-277 1 Fountain MI   543C ONVOY, LLCV - MI 348   2016-05-20   
231-277 2 Fountain MI   543C ONVOY, LLCV - MI 348   2016-05-21   
231-277 3 Fountain MI   543C ONVOY, LLCV - MI 348   2016-05-21   
231-277 4 Fountain MI   933G PEERLESS NETWORK OF MICHIGAN, LLC - MI 348   2018-12-14   
231-277 5 Fountain MI   543C ONVOY, LLCV - MI 348   2020-10-18   
231-277 6 Fountain MI   543C ONVOY, LLCV - MI 348   2020-10-18   
231-277 7 Fountain MI   508J CENTURYLINK COMMUNICATIONS, LLC 348   2017-10-04   
231-277 8 Fountain MI   792K CHARTER IP ENABLED SERVICES, LLC 348   2016-06-20   
231-277 9 Fountain MI   624H ONVOY SPECTRUM, LLC 348   2021-06-19   

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

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