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: 406

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-406 A Falmouth MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348      
231-406 0 Falmouth MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2023-08-12   
231-406 1 Falmouth MI   792K CHARTER IP ENABLED SERVICES, LLC 348   2024-04-21   
231-406 5 Falmouth MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2022-04-09   

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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