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: 341

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-341 A Lake Ann MI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 348   2025-07-06   
231-341 9 Lake Ann MI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 348   2025-07-06   

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

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