Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

Switch: CHYNWYRF6MD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
307-215 2 Casper WY 145J TERRA NOVA TELECOM INC. 654   2026-04-24   
307-290 4 Sundance WY 145J TERRA NOVA TELECOM INC. 654   2026-03-16   
307-388 5 Worland WY 145J TERRA NOVA TELECOM INC. 654   2026-03-16   
307-400 A Cheyenne WY 145J TERRA NOVA TELECOM INC. 654      
307-629 6 Newcastle WY 145J TERRA NOVA TELECOM INC. 654   2026-03-16   
307-666 4 Cheyenne WY 145J TERRA NOVA TELECOM INC. 654   2026-03-29   
307-922 9 Rock Springs WY 145J TERRA NOVA TELECOM INC. 654   2026-04-26   

Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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