Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Southeast Sheridan, WY

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
307-210 A CSPRWYMAXMD  6010 NEW CINGULAR WIRELESS PCS, LLC 654      
307-210 0   145J TERRA NOVA TELECOM INC. 654   2025-07-14   
307-210 6 CSPRWYMAXMD  6010 NEW CINGULAR WIRELESS PCS, LLC 654   2022-09-06   
307-210 7 CSPRWYMAXMD  6010 NEW CINGULAR WIRELESS PCS, LLC 654   2022-09-06   
307-210 8 CSPRWYMAXMD  6010 NEW CINGULAR WIRELESS PCS, LLC 654   2020-06-04   
307-210 9 CSPRWYMAXMD  6010 NEW CINGULAR WIRELESS PCS, LLC 654   2020-06-04   
307-737 A SESNWYXCRS0  2251 RANGE TEL COOP INC 654      

Last updated: Wed, 04 Mar 2026 03:00:52 UTC

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