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: 257

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-257 A Lake City MI LKCYMIXI2MD  116F PENINSULA FIBER NETWORK, LLC - MI 348      
231-257 0 Lake City MI LKCYMIXI2MD  116F PENINSULA FIBER NETWORK, LLC - MI 348   2019-04-19   
231-257 4 Lake City MI GDRPMIQLX5Y  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2022-05-14   

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

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