Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 317 [Rate centres in NPA 317] [Dial plan for NPA 317]

NXX: 303

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
317-303 A Plainfield IN   097D ONVOY, LLC - IN 336   2026-06-28   

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

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