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]

Region: MI

OCN: 260E YMAX COMMUNICATIONS CORP. - MI

NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date

Last updated: Sun, 17 May 2026 03:26:51 UTC

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