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: 345

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-345 A Denver CO DNVRCOMAGT7  588A ZIPPYTECH INCORPORATED 656      
720-345 0 Denver CO   588A ZIPPYTECH INCORPORATED 656   2008-02-29   
720-345 1 Denver CO   6529 T-MOBILE USA, INC. 656   2008-06-01   
720-345 2 Denver CO   6529 T-MOBILE USA, INC. 656   2008-06-01   
720-345 3 Denver CO   6529 T-MOBILE USA, INC. 656   2008-06-01   
720-345 4 Denver CO   6529 T-MOBILE USA, INC. 656   2008-06-01   
720-345 5 Denver CO   508J CENTURYLINK COMMUNICATIONS, LLC 656   2008-06-30   
720-345 6 Denver CO   9636 QWEST CORPORATION 656   2008-06-30   
720-345 7 Denver CO   6529 T-MOBILE USA, INC. 656   2008-06-21   
720-345 8 Denver CO   6529 T-MOBILE USA, INC. 656   2008-06-21   
720-345 9 Denver CO   6529 T-MOBILE USA, INC. 656   2008-06-21   

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

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