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Columbia, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
443-319 5 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2005-03-10   
443-319 6 PIVLMDPKXHX  829J PAETEC ITEL, LLC 238      
443-319 7 BLTMMDCH40Z  5562 METROPCS, INC. 238   2016-02-03   
443-319 8 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2010-11-19   
443-319 9 PIVLMDPKXHX  829J PAETEC ITEL, LLC 238      
443-367 A CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
443-367 0 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
443-367 1 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-07-02   
443-367 2 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
443-367 3 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
443-367 4 PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2007-06-15   
443-367 5 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
443-367 6   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-03-28   
443-367 7 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
443-367 8 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-10-28   
443-367 9 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2011-04-03   
443-393 A BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-393 0 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-01-08   
443-393 1 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-01-08   
443-393 2 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-09-10   
443-393 3 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-09-10   
443-393 4 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-393 5 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-393 6 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-05-08   
443-393 7 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2011-04-03   
443-393 8 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-393 9 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-430 A BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-430 0 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-430 1   515J IP HORIZON LLC 238   2016-10-14   
443-430 2 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2005-08-14   
443-430 3 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-430 4 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2016-09-26   
443-430 5 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2016-09-26   
443-430 6 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2005-08-14   
443-430 7 BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2008-05-30   
443-430 8 BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2006-03-11   
443-430 9 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-472 A BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-472 0 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-06-03   
443-472 1 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2003-11-19   
443-472 2 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2003-11-03   
443-472 3 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-08-02   
443-472 4 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-472 5 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-11-04   
443-472 6 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2005-01-02   
443-472 7 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-02-28   
443-472 8 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2005-01-02   
443-472 9 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2005-11-01   
443-518 A CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      

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Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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