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: 612

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-612 A Denver CO DNVRCOII3MD  6529 T-MOBILE USA, INC. 656      
720-612 0 Denver CO   6529 T-MOBILE USA, INC. 656   2011-09-05   
720-612 1 Denver CO   6529 T-MOBILE USA, INC. 656   2011-09-05   
720-612 2 Denver CO   6529 T-MOBILE USA, INC. 656   2011-09-05   
720-612 3 Denver CO   6529 T-MOBILE USA, INC. 656   2011-09-05   
720-612 4 Denver CO   318J COMCAST IP PHONE, LLC 656   2012-07-01   
720-612 5 Denver CO   4574 LEVEL 3 TELECOM OF COLORADO, LLC - CO 656   2012-06-08   
720-612 6 Denver CO   4574 LEVEL 3 TELECOM OF COLORADO, LLC - CO 656   2012-06-08   
720-612 7 Denver CO   318J COMCAST IP PHONE, LLC 656   2012-07-01   
720-612 8 Denver CO   6529 T-MOBILE USA, INC. 656   2012-06-27   
720-612 9 Denver CO   6529 T-MOBILE USA, INC. 656   2011-09-05   

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

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