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: 541

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-541 A Cockeysville MD   829J PAETEC ITEL, LLC 238   2025-04-01   
443-541 0 Cockeysville MD   829J PAETEC ITEL, LLC 238      
443-541 1 Cockeysville MD   829J PAETEC ITEL, LLC 238      
443-541 2 Cockeysville MD   829J PAETEC ITEL, LLC 238      
443-541 3 Cockeysville MD   829J PAETEC ITEL, LLC 238      
443-541 4 Cockeysville MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2003-08-20   
443-541 5 Cockeysville MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-01-10   
443-541 6 Cockeysville MD   515J IP HORIZON LLC 238   2016-10-14   
443-541 7 Cockeysville MD BLTMMDCHX7X  073H TELNYX LLC 238   2017-03-14   
443-541 8 Cockeysville MD   829J PAETEC ITEL, LLC 238      
443-541 9 Cockeysville MD   829J PAETEC ITEL, LLC 238      

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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