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: 552

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-552 A Charlevoix MI   2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2025-09-21   
231-552 9 Charlevoix MI   2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2025-09-21   

Last updated: Mon, 15 Sep 2025 02:24:40 UTC

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