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: 304

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
307-304 A Jeffrey City WY CSPRWYMAXMD  6010 NEW CINGULAR WIRELESS PCS, LLC 654      
307-304 8 Jeffrey City WY CSPRWYMAXMD  6010 NEW CINGULAR WIRELESS PCS, LLC 654   2020-11-16   
307-304 9 Jeffrey City WY CSPRWYMAXMD  6010 NEW CINGULAR WIRELESS PCS, LLC 654   2020-11-16   

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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