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: 451

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
307-451 A Rock Springs WY CHYNWYRF5MD  197D VONAGE AMERICA LLC 654   2024-06-27   
307-451 0 Rock Springs WY CHYNWYMAX2X  450F ONVOY, LLC - WY 654   2025-05-10   
307-451 1 Rock Springs WY CHYNWYMAXIX  6566 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY 654   2025-06-27   
307-451 9 Rock Springs WY CHYNWYRF5MD  197D VONAGE AMERICA LLC 654   2024-06-27   

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

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