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: 431

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-431 A Clam River MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2024-12-09   
231-431 0 Clam River MI GDRPMIBL00Z  991E BANDWIDTH.COM CLEC, LLC - MI 348   2021-08-23   
231-431 1 Clam River MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2023-08-26   
231-431 3 Clam River MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-07-24   
231-431 4 Clam River MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2022-03-04   
231-431 5 Clam River MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-09-10   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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