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 HDSNCOMARS1  9636 QWEST CORPORATION 656      
303-536 1 Hudson CO DNVRCOMAXGZ  078F BANDWIDTH.COM CLEC, LLC - CO 656   2014-08-15   
303-536 2 Hudson CO HDSNCOMARS1  9636 QWEST CORPORATION 656      
303-536 3 Hudson CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2010-11-28   
303-536 4 Hudson CO HDSNCOMARS1  9636 QWEST CORPORATION 656      
303-536 5 Hudson CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2004-11-11   
303-536 6 Hudson CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2014-01-11   
303-536 7 Hudson CO DNVRCOMAXGZ  078F BANDWIDTH.COM CLEC, LLC - CO 656   2014-04-14   
303-536 8 Hudson CO DNVTCOZIDS1  026D ONVOY, LLC - CO 656   2014-06-12   
303-536 9 Hudson CO HDSNCOMARS1  9636 QWEST CORPORATION 656      

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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