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Westminster, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
443-244 9   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-02-14   
443-289 A BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238      
443-289 0   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-09-15   
443-289 1   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-09-15   
443-289 2   7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2011-06-30   
443-289 3   7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2011-06-30   
443-289 4   5562 METROPCS, INC. 238   2011-10-10   
443-289 5   5562 METROPCS, INC. 238   2011-10-10   
443-289 6   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-10-10   
443-289 7   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-11-23   
443-289 8   318J COMCAST IP PHONE, LLC 238   2012-11-24   
443-289 9   318J COMCAST IP PHONE, LLC 238   2014-02-19   
443-293 A   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-293 0   876D ONVOY, LLC - MD 238   2025-09-28   
443-293 1   876D ONVOY, LLC - MD 238   2025-10-30   
443-293 2   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-01-20   
443-293 3   829J PAETEC ITEL, LLC 238   2006-07-14   
443-293 4   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2026-01-08   
443-293 5   876D ONVOY, LLC - MD 238   2021-09-23   
443-293 6   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-09-15   
443-293 7   318J COMCAST IP PHONE, LLC 238   2008-02-22   
443-293 8   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2007-05-14   
443-340 A BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-368 A BLTMMD91GT0  2593 CORE COMMUNICATIONS, INC.- MD 238      
443-487 A BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-487 0   876D ONVOY, LLC - MD 238   2022-10-16   
443-487 1   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2008-03-03   
443-487 2   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2008-04-04   
443-487 3   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2009-02-02   
443-487 4   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-05-05   
443-487 5   829J PAETEC ITEL, LLC 238   2002-11-16   
443-487 6   071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-09-03   
443-487 7   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2007-09-21   
443-487 8   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2002-11-25   
443-487 9   318J COMCAST IP PHONE, LLC 238   2021-10-08   
443-536 A BLTMMDCH40Z  5562 METROPCS, INC. 238      
443-536 0   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2008-12-10   
443-536 1   5562 METROPCS, INC. 238      
443-536 2   5562 METROPCS, INC. 238   2005-01-18   
443-536 3   5562 METROPCS, INC. 238      
443-536 4   5562 METROPCS, INC. 238   2007-08-22   
443-536 5   5562 METROPCS, INC. 238      
443-536 6   5562 METROPCS, INC. 238      
443-536 7   5562 METROPCS, INC. 238   2007-08-22   
443-536 8   5562 METROPCS, INC. 238   2006-06-07   
443-536 9   5562 METROPCS, INC. 238      
443-547 A BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-547 0   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2009-07-06   
443-547 1   5562 METROPCS, INC. 238   2009-09-09   
443-547 2   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2009-10-02   

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

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