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: 975

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-975 A Denver CO DNVRCOETPS0  3467 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 656      
720-975 0 Denver CO   3467 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 656      
720-975 1 Denver CO   3467 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 656      
720-975 2 Denver CO   3467 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 656      
720-975 3 Denver CO   6529 T-MOBILE USA, INC. 656   2008-05-24   
720-975 4 Denver CO   6529 T-MOBILE USA, INC. 656   2008-05-24   
720-975 5 Denver CO   6529 T-MOBILE USA, INC. 656   2008-07-31   
720-975 6 Denver CO   6529 T-MOBILE USA, INC. 656   2009-01-20   
720-975 7 Denver CO   6529 T-MOBILE USA, INC. 656   2009-07-29   
720-975 8 Denver CO   026D ONVOY, LLC - CO 656   2008-09-27   
720-975 9 Denver CO   3467 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 656   2007-02-12   

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

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