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: 338

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-338 A Baldwin MI GDRPMIBL00Z  991E BANDWIDTH.COM CLEC, LLC - MI 348      
231-338 0 Baldwin MI   939H COMMIO, LLC 348   2022-11-05   
231-338 3 Baldwin MI   516C AT&T CORP. 348   2011-08-23   
231-338 6 Baldwin MI   991E BANDWIDTH.COM CLEC, LLC - MI 348   2013-01-11   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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