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: 831

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-831 A Denver CO FTCLCOMAAMD  7378 TELEPORT COMMUNICATIONS AMERICA, LLC - CO 656      
720-831 0 Denver CO   6529 T-MOBILE USA, INC. 656   2021-12-25   
720-831 1 Denver CO   6529 T-MOBILE USA, INC. 656   2021-12-25   
720-831 2 Denver CO   6529 T-MOBILE USA, INC. 656   2021-12-25   
720-831 3 Denver CO   6529 T-MOBILE USA, INC. 656   2021-12-25   
720-831 4 Denver CO   6529 T-MOBILE USA, INC. 656   2021-12-25   
720-831 5 Denver CO   7378 TELEPORT COMMUNICATIONS AMERICA, LLC - CO 656   2021-12-24   
720-831 6 Denver CO   7378 TELEPORT COMMUNICATIONS AMERICA, LLC - CO 656   2021-12-24   
720-831 7 Denver CO   6529 T-MOBILE USA, INC. 656   2021-12-25   
720-831 8 Denver CO   6529 T-MOBILE USA, INC. 656   2021-12-25   
720-831 9 Denver CO   6529 T-MOBILE USA, INC. 656   2021-12-25   

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

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