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: 673

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-673 A Denver CO DNVTCOZIBMD  114J EXIANT COMMUNICATIONS LLC 656      
720-673 0 Denver CO   073H TELNYX LLC 656   2019-10-25   
720-673 1 Denver CO   114J EXIANT COMMUNICATIONS LLC 656   2019-10-21   
720-673 2 Denver CO   6529 T-MOBILE USA, INC. 656   2019-12-14   
720-673 3 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2019-10-22   
720-673 4 Denver CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2019-10-22   
720-673 5 Denver CO   6529 T-MOBILE USA, INC. 656   2019-12-14   
720-673 6 Denver CO   6529 T-MOBILE USA, INC. 656   2019-12-14   
720-673 7 Denver CO   6529 T-MOBILE USA, INC. 656   2019-12-14   
720-673 8 Denver CO   078F BANDWIDTH.COM CLEC, LLC - CO 656   2019-10-24   
720-673 9 Denver CO   078F BANDWIDTH.COM CLEC, LLC - CO 656   2019-10-24   

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

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