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: 579

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-579 A Essex MD   829J PAETEC ITEL, LLC 238   2025-04-01   
443-579 0 Essex MD   829J PAETEC ITEL, LLC 238      
443-579 1 Essex MD   829J PAETEC ITEL, LLC 238      
443-579 2 Essex MD   829J PAETEC ITEL, LLC 238      
443-579 3 Essex MD   829J PAETEC ITEL, LLC 238      
443-579 4 Essex MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-06-26   
443-579 5 Essex MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2008-12-11   
443-579 6 Essex MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2008-07-17   
443-579 7 Essex MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-10-28   
443-579 8 Essex MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-02-26   
443-579 9 Essex MD   829J PAETEC ITEL, LLC 238      

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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