Local Calling Guide

Area code/prefix search

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NPA: 517 [Rate centres in NPA 517] [Dial plan for NPA 517]

NXX: 957

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
517-957 A Onondaga MI MDTPMICODS0  3535 ACD TELECOM, INC. - MI 346      

Last updated: Fri, 10 Jul 2026 02:55:48 UTC

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