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: 648

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-648 A Denver CO ELBRCOMARS2  9636 QWEST CORPORATION 656      
303-648 0 Denver CO   9636 QWEST CORPORATION 656      
303-648 1 Denver CO   6010 NEW CINGULAR WIRELESS PCS, LLC 656   2006-09-24   
303-648 2 Denver CO   624H ONVOY SPECTRUM, LLC 656   2024-07-08   
303-648 3 Denver CO   9636 QWEST CORPORATION 656      
303-648 4 Denver CO   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 656   2005-02-27   
303-648 5 Denver CO   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 656   2005-02-27   
303-648 6 Denver CO   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 656   2005-02-27   
303-648 7 Denver CO   624H ONVOY SPECTRUM, LLC 656   2024-07-08   
303-648 8 Denver CO   9636 QWEST CORPORATION 656      
303-648 9 Denver CO   9636 QWEST CORPORATION 656      

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

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