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: 581

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-581 A Alba MI   792K CHARTER IP ENABLED SERVICES, LLC 348      
231-581 0 Alba MI   792K CHARTER IP ENABLED SERVICES, LLC 348      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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