Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 517 [Rate centres in NPA 517] [Dial plan for NPA 517]

NXX: 277

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
517-277 A De Witt MI LNNHMIQD0MD  591C WESTPHALIA BROADBAND, INC. - MI 346      

Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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