Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Hamilton Dome, WY

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
307-238 A CSPRWYMAXMD  6010 NEW CINGULAR WIRELESS PCS, LLC 654      
307-238 6 CSPRWYMAXMD  6010 NEW CINGULAR WIRELESS PCS, LLC 654   2017-10-06   
307-867 A BASNWYXCDS1  2296 TRI-COUNTY TEL. ASSN., INC. 654      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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