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: 778

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-778 A Denver CO DNVRCOMAXGZ  078F BANDWIDTH.COM CLEC, LLC - CO 656      
720-778 0 Denver CO   078F BANDWIDTH.COM CLEC, LLC - CO 656   2014-11-24   
720-778 1 Denver CO   078F BANDWIDTH.COM CLEC, LLC - CO 656   2014-11-24   
720-778 2 Denver CO   026D ONVOY, LLC - CO 656   2014-12-02   
720-778 3 Denver CO   026D ONVOY, LLC - CO 656   2014-12-02   
720-778 4 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2015-04-24   
720-778 5 Denver CO   508J CENTURYLINK COMMUNICATIONS, LLC 656   2015-07-01   
720-778 6 Denver CO   6010 NEW CINGULAR WIRELESS PCS, LLC 656   2014-11-25   
720-778 7 Denver CO   6010 NEW CINGULAR WIRELESS PCS, LLC 656   2014-11-25   
720-778 8 Denver CO   026D ONVOY, LLC - CO 656   2015-08-03   
720-778 9 Denver CO   026D ONVOY, LLC - CO 656   2015-08-03   

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

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