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: 354

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-354 A Denver CO AURSCOFWDS0  4574 LEVEL 3 TELECOM OF COLORADO, LLC - CO 656      
720-354 0 Denver CO   6529 T-MOBILE USA, INC. 656   2011-08-23   
720-354 1 Denver CO   6529 T-MOBILE USA, INC. 656   2011-08-23   
720-354 2 Denver CO   6529 T-MOBILE USA, INC. 656   2011-08-23   
720-354 3 Denver CO   4574 LEVEL 3 TELECOM OF COLORADO, LLC - CO 656   2011-08-21   
720-354 4 Denver CO   3467 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 656   2011-08-23   
720-354 5 Denver CO   026D ONVOY, LLC - CO 656   2011-09-05   
720-354 6 Denver CO   6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2011-09-05   
720-354 7 Denver CO   6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2011-09-05   
720-354 8 Denver CO   6529 T-MOBILE USA, INC. 656   2011-08-23   
720-354 9 Denver CO   026D ONVOY, LLC - CO 656   2011-09-05   

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

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