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: 278

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-278 A Denver CO AURSCOFWDS0  4574 LEVEL 3 TELECOM OF COLORADO, LLC - CO 656      
720-278 0 Denver CO   6529 T-MOBILE USA, INC. 656   2006-09-16   
720-278 1 Denver CO   6529 T-MOBILE USA, INC. 656   2005-05-09   
720-278 2 Denver CO   4574 LEVEL 3 TELECOM OF COLORADO, LLC - CO 656      
720-278 3 Denver CO   6529 T-MOBILE USA, INC. 656   2006-09-16   
720-278 4 Denver CO   6529 T-MOBILE USA, INC. 656   2006-11-02   
720-278 5 Denver CO   6529 T-MOBILE USA, INC. 656   2006-11-02   
720-278 6 Denver CO   6529 T-MOBILE USA, INC. 656   2006-11-02   
720-278 7 Denver CO   026D ONVOY, LLC - CO 656   2007-04-30   
720-278 8 Denver CO   6529 T-MOBILE USA, INC. 656   2007-04-02   
720-278 9 Denver CO   6529 T-MOBILE USA, INC. 656   2007-03-09   

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

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