Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 303 [Rate centres in NPA 303] [Dial plan for NPA 303]

NXX: 658

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-658 A Denver CO LTTNCOMADS0  9636 QWEST CORPORATION 656      
303-658 0 Denver CO   318J COMCAST IP PHONE, LLC 656   2009-06-18   
303-658 1 Denver CO   9636 QWEST CORPORATION 656      
303-658 2 Denver CO   9636 QWEST CORPORATION 656      
303-658 3 Denver CO   9636 QWEST CORPORATION 656      
303-658 4 Denver CO   9636 QWEST CORPORATION 656      
303-658 5 Denver CO   9636 QWEST CORPORATION 656      
303-658 6 Denver CO   9636 QWEST CORPORATION 656      
303-658 7 Denver CO   9636 QWEST CORPORATION 656      
303-658 8 Denver CO   9636 QWEST CORPORATION 656      
303-658 9 Denver CO   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 656   2009-02-23   

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

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