Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 720 [Rate centres in NPA 720] [Dial plan for NPA 720]

NXX: 206

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-206 A Denver CO DNVRCO37DS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 656      
720-206 0 Denver CO   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 656      
720-206 1 Denver CO   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 656      
720-206 2 Denver CO   732J NUSO, LLC 656   2025-07-19   
720-206 4 Denver CO   6529 T-MOBILE USA, INC. 656   2004-09-17   
720-206 5 Denver CO   6529 T-MOBILE USA, INC. 656   2004-09-17   
720-206 6 Denver CO   6010 NEW CINGULAR WIRELESS PCS, LLC 656   2007-10-20   
720-206 7 Denver CO   6529 T-MOBILE USA, INC. 656   2004-11-12   
720-206 8 Denver CO   6529 T-MOBILE USA, INC. 656   2005-05-28   
720-206 9 Denver CO   6529 T-MOBILE USA, INC. 656   2005-02-04   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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