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: 421

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
307-421 A Cheyenne WY CHYNWYMAXIX  6566 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY 654      

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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