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: 277

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-277 A Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
720-277 0 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
720-277 1 Denver CO   6529 T-MOBILE USA, INC. 656   2005-02-04   
720-277 2 Denver CO   6529 T-MOBILE USA, INC. 656   2005-02-04   
720-277 3 Denver CO   318J COMCAST IP PHONE, LLC 656   2002-12-16   
720-277 4 Denver CO   6529 T-MOBILE USA, INC. 656   2009-10-23   
720-277 5 Denver CO   6529 T-MOBILE USA, INC. 656   2003-12-14   
720-277 6 Denver CO   6529 T-MOBILE USA, INC. 656   2003-12-14   
720-277 7 Denver CO   6529 T-MOBILE USA, INC. 656   2005-03-18   
720-277 8 Denver CO   6529 T-MOBILE USA, INC. 656   2005-03-18   
720-277 9 Denver CO   078F BANDWIDTH.COM CLEC, LLC - CO 656   2010-02-19   

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

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