Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 307 [Rate centres in NPA 307] [Dial plan for NPA 307]

NXX: 856

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
307-856 A Riverton WY RVTNWYMADS0  9636 QWEST CORPORATION 654      

Last updated: Wed, 04 Mar 2026 03:00:52 UTC

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