Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

NXX: 317

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-317 A Chase MD   071F BANDWIDTH.COM CLEC, LLC - MD 238      
443-317 2 Chase MD   876D ONVOY, LLC - MD 238   2012-10-08   
443-317 3 Chase MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-01-09   
443-317 6 Chase MD   318J COMCAST IP PHONE, LLC 238   2015-08-05   
443-317 7 Chase MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2016-07-14   
443-317 8 Chase MD   318J COMCAST IP PHONE, LLC 238   2007-04-12   
443-317 9 Chase MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2014-04-27   

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

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