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: 297

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
307-297 A Green River WY EVTNWYBHW00  1772 UINTAH BASIN ELECTRONIC TELECOMMUNICATIONS 654   2024-01-16   

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

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