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: 645

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-645 A Denver CO DNVRCOII3MD  6529 T-MOBILE USA, INC. 656      
720-645 0 Denver CO   6010 NEW CINGULAR WIRELESS PCS, LLC 656   2014-05-06   
720-645 1 Denver CO   318J COMCAST IP PHONE, LLC 656   2014-05-14   
720-645 2 Denver CO   318J COMCAST IP PHONE, LLC 656   2014-05-14   
720-645 3 Denver CO   6529 T-MOBILE USA, INC. 656   2014-05-04   
720-645 4 Denver CO   6529 T-MOBILE USA, INC. 656   2014-05-04   
720-645 5 Denver CO   6529 T-MOBILE USA, INC. 656   2014-05-04   
720-645 6 Denver CO   6529 T-MOBILE USA, INC. 656   2014-05-04   
720-645 7 Denver CO   6529 T-MOBILE USA, INC. 656   2014-05-04   
720-645 8 Denver CO   6529 T-MOBILE USA, INC. 656   2014-05-04   
720-645 9 Denver CO   6529 T-MOBILE USA, INC. 656   2014-05-04   

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

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