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: 579

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-579 A Denver CO DNVRCO37DS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 656      
720-579 0 Denver CO   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 656      
720-579 1 Denver CO   6529 T-MOBILE USA, INC. 656   2007-09-02   
720-579 2 Denver CO   6529 T-MOBILE USA, INC. 656   2007-11-02   
720-579 3 Denver CO   6529 T-MOBILE USA, INC. 656   2007-11-30   
720-579 4 Denver CO   6529 T-MOBILE USA, INC. 656   2009-07-17   
720-579 5 Denver CO   6529 T-MOBILE USA, INC. 656   2009-07-17   
720-579 6 Denver CO   6529 T-MOBILE USA, INC. 656   2008-01-18   
720-579 7 Denver CO   6529 T-MOBILE USA, INC. 656   2008-02-04   
720-579 8 Denver CO   6529 T-MOBILE USA, INC. 656   2008-03-09   
720-579 9 Denver CO   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 656      

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

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