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: 251

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-251 A Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
720-251 0 Denver CO   6529 T-MOBILE USA, INC. 656   2005-10-02   
720-251 1 Denver CO   6529 T-MOBILE USA, INC. 656   2005-06-10   
720-251 2 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2004-09-18   
720-251 3 Denver CO   6529 T-MOBILE USA, INC. 656   2005-10-02   
720-251 4 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
720-251 5 Denver CO   6529 T-MOBILE USA, INC. 656   2006-03-05   
720-251 6 Denver CO   6529 T-MOBILE USA, INC. 656   2006-08-06   
720-251 7 Denver CO   490J DISH WIRELESS, LLC 656   2024-09-07   
720-251 8 Denver CO   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 656   2006-07-09   
720-251 9 Denver CO   6529 T-MOBILE USA, INC. 656   2006-08-06   

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

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