Local Calling Guide

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

NXX: 503

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-503 A Dundalk MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-503 0 Dundalk MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-503 1 Dundalk MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-503 2 Dundalk MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-503 3 Dundalk MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-02-11   
443-503 4 Dundalk MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2003-02-20   
443-503 5 Dundalk MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2006-09-18   
443-503 6 Dundalk MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2006-09-18   
443-503 7 Dundalk MD PIVLMDPKFMD  9170 BROADVIEW NETWORKS, INC. - MD 238   2009-04-20   
443-503 8 Dundalk MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2013-02-04   
443-503 9 Dundalk MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2020-03-17   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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