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NPA: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

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NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
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 PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2009-04-20   
443-503 8 Dundalk MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2013-02-04   
443-503 9 Dundalk MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2020-03-17   
443-504 A Fallston MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238   2025-04-01   
443-504 0 Fallston MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-504 1 Fallston MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2004-03-29   
443-504 2 Fallston MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-05-02   
443-504 3 Fallston MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-07-02   
443-504 4 Fallston MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-01-19   
443-504 5 Fallston MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-02-28   
443-504 6 Fallston MD BLTMMDCH25Z  8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 238   2015-06-14   
443-504 7 Fallston MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2005-04-01   
443-504 8 Fallston MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-08-02   
443-504 9 Fallston MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-09-29   
443-505 A Essex MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-505 0 Essex MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-05-01   
443-505 1 Essex MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-05-01   
443-505 2 Essex MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2011-12-24   
443-505 3 Essex MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2014-03-20   
443-505 4 Essex MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-09-29   
443-505 5 Essex MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-01-26   
443-505 6 Essex MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2018-10-18   
443-505 7 Essex MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2008-05-16   
443-505 8 Essex MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2014-09-21   
443-505 9 Essex MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2019-10-07   
443-506 A Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-506 0 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-506 1 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-506 2 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-506 3 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-506 4 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-506 5 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-506 6 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-506 7 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-506 8 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-506 9 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-507 A Hampstead MD BLTMMDFMDS0  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-507 0 Hampstead MD HMPSMDHERS1  9212 VERIZON MARYLAND, INC. 238   2003-10-17   
443-507 1 Hampstead MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2003-07-20   
443-507 3 Hampstead MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2004-03-29   
443-507 4 Hampstead MD BLTMMD91DS2  2596 QUANTUM TELECOMMUNICATIONS, INC. - MD 238   2016-01-31   
443-507 5 Hampstead MD HMPSMDHERS1  9212 VERIZON MARYLAND, INC. 238   2005-05-27   
443-507 6 Hampstead MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2009-06-13   
443-507 7 Hampstead MD   145J TERRA NOVA TELECOM INC. 238   2024-02-15   
443-507 8 Hampstead MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-07-02   
443-507 9 Hampstead MD BLTMMDFMDS0  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      

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Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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