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: 439

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
517-439 A Hillsdale MI HLDLMIMNRSA  9323 MICHIGAN BELL TEL CO 346      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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