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: 428

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
307-428 A Douglas WY CSPRWYMAXEX  6529 T-MOBILE USA, INC. 654   2024-02-03   
307-428 0 Douglas WY   450F ONVOY, LLC - WY 654      
307-428 1 Douglas WY   450F ONVOY, LLC - WY 654      
307-428 8 Douglas WY CHYNWYMAXIX  6566 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY 654      
307-428 9 Douglas WY CSPRWYMAXEX  6529 T-MOBILE USA, INC. 654      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

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