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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
443-536 0 Westminster MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2008-12-10   
443-536 1 Westminster MD   5562 METROPCS, INC. 238      
443-536 2 Westminster MD   5562 METROPCS, INC. 238   2005-01-18   
443-536 3 Westminster MD   5562 METROPCS, INC. 238      
443-536 4 Westminster MD   5562 METROPCS, INC. 238   2007-08-22   
443-536 5 Westminster MD   5562 METROPCS, INC. 238      
443-536 6 Westminster MD   5562 METROPCS, INC. 238      
443-536 7 Westminster MD   5562 METROPCS, INC. 238   2007-08-22   
443-536 8 Westminster MD   5562 METROPCS, INC. 238   2006-06-07   
443-536 9 Westminster MD   5562 METROPCS, INC. 238      
443-537 A Columbia MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-537 0 Columbia MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2009-10-30   
443-537 1 Columbia MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2009-10-25   
443-537 2 Columbia MD   829J PAETEC ITEL, LLC 238   2011-03-11   
443-537 3 Columbia MD   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-06-03   
443-537 4 Columbia MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2009-07-13   
443-537 5 Columbia MD   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-06-14   
443-537 6 Columbia MD   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-06-14   
443-537 7 Columbia MD   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-06-14   
443-537 8 Columbia MD   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-06-14   
443-537 9 Columbia MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-02-05   
443-538 A Columbia MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-539 A Columbia MD   829J PAETEC ITEL, LLC 238   2025-04-01   
443-539 0 Columbia MD   829J PAETEC ITEL, LLC 238      
443-539 1 Columbia MD   829J PAETEC ITEL, LLC 238      
443-539 2 Columbia MD   829J PAETEC ITEL, LLC 238      
443-539 3 Columbia MD   829J PAETEC ITEL, LLC 238      
443-539 4 Columbia MD   829J PAETEC ITEL, LLC 238   2006-08-15   
443-539 5 Columbia MD   7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2008-10-01   
443-539 6 Columbia MD   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-10-28   
443-539 7 Columbia MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2010-02-15   
443-539 8 Columbia MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2008-02-13   
443-539 9 Columbia MD   829J PAETEC ITEL, LLC 238      
443-540 A Baltimore MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
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   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2003-08-20   
443-541 5 Cockeysville MD   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   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      
443-542 A Columbia MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238      
443-542 0 Columbia MD   318J COMCAST IP PHONE, LLC 238      
443-542 1 Columbia MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2004-11-25   
443-542 2 Columbia MD   318J COMCAST IP PHONE, LLC 238      
443-542 3 Columbia MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-03-12   

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Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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