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: 536

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-536 A Hudson CO HDSNCOMARS1  9636 QWEST CORPORATION 656      
303-536 0 Hudson CO   9636 QWEST CORPORATION 656      
303-536 1 Hudson CO   078F BANDWIDTH.COM CLEC, LLC - CO 656   2014-08-15   
303-536 2 Hudson CO   9636 QWEST CORPORATION 656      
303-536 3 Hudson CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2010-11-28   
303-536 4 Hudson CO   9636 QWEST CORPORATION 656      
303-536 5 Hudson CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2004-11-11   
303-536 6 Hudson CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2014-01-11   
303-536 7 Hudson CO   078F BANDWIDTH.COM CLEC, LLC - CO 656   2014-04-14   
303-536 8 Hudson CO   026D ONVOY, LLC - CO 656   2014-06-12   
303-536 9 Hudson CO   9636 QWEST CORPORATION 656      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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