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: 342

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-342 A Denver CO FTCLCOMAAMD  7378 TELEPORT COMMUNICATIONS AMERICA, LLC - CO 656      
720-342 0 Denver CO   7421 AT&T - LOCAL 656   2009-06-06   
720-342 1 Denver CO   7421 AT&T - LOCAL 656   2009-06-06   
720-342 2 Denver CO   7421 AT&T - LOCAL 656   2009-06-06   
720-342 3 Denver CO   7421 AT&T - LOCAL 656   2009-06-06   
720-342 4 Denver CO   7421 AT&T - LOCAL 656   2009-06-06   
720-342 5 Denver CO   7421 AT&T - LOCAL 656   2009-06-06   
720-342 6 Denver CO   7421 AT&T - LOCAL 656   2009-06-06   
720-342 7 Denver CO   7421 AT&T - LOCAL 656   2009-06-06   
720-342 8 Denver CO   7421 AT&T - LOCAL 656   2009-06-06   
720-342 9 Denver CO   7421 AT&T - LOCAL 656   2009-06-06   

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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