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: 400

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-400 A Denver CO DNVRCOII3MD  6529 T-MOBILE USA, INC. 656      
720-400 0 Denver CO   6529 T-MOBILE USA, INC. 656   2010-12-12   
720-400 1 Denver CO   6529 T-MOBILE USA, INC. 656   2010-12-12   
720-400 2 Denver CO   6529 T-MOBILE USA, INC. 656   2010-12-12   
720-400 3 Denver CO   6567 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CO 656   2011-09-03   
720-400 4 Denver CO   6529 T-MOBILE USA, INC. 656   2011-10-31   
720-400 5 Denver CO   6529 T-MOBILE USA, INC. 656   2011-10-31   
720-400 6 Denver CO   6529 T-MOBILE USA, INC. 656   2011-10-31   
720-400 7 Denver CO   078F BANDWIDTH.COM CLEC, LLC - CO 656   2011-01-10   
720-400 8 Denver CO   078F BANDWIDTH.COM CLEC, LLC - CO 656   2011-01-10   
720-400 9 Denver CO   6529 T-MOBILE USA, INC. 656   2010-12-12   

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

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