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.
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Switch: DNVRCOMA61Z

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
970-303 2 Windsor CO 053L TELIMIZE, LLC 656   2025-10-18   
970-303 4 Windsor CO 053L TELIMIZE, LLC 656   2025-10-18   
970-303 5 Windsor CO 053L TELIMIZE, LLC 656   2025-10-18   
970-303 6 Windsor CO 053L TELIMIZE, LLC 656   2025-10-18   
970-303 7 Windsor CO 053L TELIMIZE, LLC 656   2025-10-18   
983-220 A Denver CO 053L TELIMIZE, LLC 656   2025-09-11   
983-220 2 Denver CO 053L TELIMIZE, LLC 656   2025-09-11   
983-220 3 Denver CO 053L TELIMIZE, LLC 656   2025-09-11   

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

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