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: 508

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-508 A Denver CO DNVRCOETPS0  3467 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 656      
720-508 0 Denver CO   6529 T-MOBILE USA, INC. 656   2012-09-11   
720-508 1 Denver CO   026D ONVOY, LLC - CO 656   2012-08-24   
720-508 2 Denver CO   026D ONVOY, LLC - CO 656   2012-08-24   
720-508 3 Denver CO   318J COMCAST IP PHONE, LLC 656   2012-08-24   
720-508 4 Denver CO   318J COMCAST IP PHONE, LLC 656   2012-08-24   
720-508 5 Denver CO   026D ONVOY, LLC - CO 656   2012-08-24   
720-508 6 Denver CO   9636 QWEST CORPORATION 656   2012-09-22   
720-508 7 Denver CO   829J PAETEC ITEL, LLC 656   2012-09-22   
720-508 8 Denver CO   3467 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 656   2012-08-23   
720-508 9 Denver CO   6529 T-MOBILE USA, INC. 656   2012-08-24   

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

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