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: 231

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-231 A Essex MD BLTMMDCHCMD  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-231 0 Essex MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-02-11   
443-231 1 Essex MD   829J PAETEC ITEL, LLC 238   2005-04-29   
443-231 2 Essex MD BLTMMDCHCMD  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-231 3 Essex MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-04-24   
443-231 4 Essex MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2003-02-20   
443-231 5 Essex MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2005-03-10   
443-231 6 Essex MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2006-06-20   
443-231 7 Essex MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2006-06-20   
443-231 8 Essex MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2006-08-25   
443-231 9 Essex MD   515J IP HORIZON LLC 238   2016-05-31   

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

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