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: 266

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-266 A Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
720-266 0 Denver CO   6529 T-MOBILE USA, INC. 656   2009-07-17   
720-266 1 Denver CO   6529 T-MOBILE USA, INC. 656   2009-07-17   
720-266 2 Denver CO   829J PAETEC ITEL, LLC 656   2008-12-19   
720-266 3 Denver CO   6010 NEW CINGULAR WIRELESS PCS, LLC 656   2007-05-19   
720-266 4 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
720-266 5 Denver CO   3467 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 656   2005-01-22   
720-266 6 Denver CO   3467 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 656   2005-08-25   
720-266 7 Denver CO   6529 T-MOBILE USA, INC. 656   2006-01-09   
720-266 8 Denver CO   6010 NEW CINGULAR WIRELESS PCS, LLC 656   2007-04-02   
720-266 9 Denver CO   6010 NEW CINGULAR WIRELESS PCS, LLC 656   2007-04-02   

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

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