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: 666

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
307-666 A Cheyenne WY CHYNWYRF7MD  965H FRACTEL, LLC 654      
307-666 0 Cheyenne WY   450F ONVOY, LLC - WY 654   2023-10-28   
307-666 6 Cheyenne WY   965H FRACTEL, LLC 654   2019-07-20   
307-666 7 Cheyenne WY   145J TERRA NOVA TELECOM INC. 654   2025-08-04   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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