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: 318

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-318 A Cockeysville MD   829J PAETEC ITEL, LLC 238   2025-04-01   
443-318 0 Cockeysville MD   829J PAETEC ITEL, LLC 238      
443-318 1 Cockeysville MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2020-09-04   
443-318 2 Cockeysville MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2020-07-10   
443-318 3 Cockeysville MD   5562 METROPCS, INC. 238   2015-07-03   
443-318 4 Cockeysville MD   318J COMCAST IP PHONE, LLC 238   2005-03-10   
443-318 5 Cockeysville MD   5562 METROPCS, INC. 238   2017-01-18   
443-318 6 Cockeysville MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2020-09-28   
443-318 7 Cockeysville MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2007-12-04   
443-318 8 Cockeysville MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-10-14   
443-318 9 Cockeysville MD   829J PAETEC ITEL, LLC 238      

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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