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: 387

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
517-387 A Hillsdale MI LNNGMIMNX4Z  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 346   2026-06-11   
517-387 9 Hillsdale MI LNNGMIMNX4Z  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 346   2026-06-11   

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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