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Columbia, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
443-319 5   318J COMCAST IP PHONE, LLC 238   2005-03-10   
443-319 6   829J PAETEC ITEL, LLC 238      
443-319 7   5562 METROPCS, INC. 238   2016-02-03   
443-319 8   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2010-11-19   
443-319 9   829J PAETEC ITEL, LLC 238      
443-367 A CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
443-367 0   9212 VERIZON MARYLAND, INC. 238      
443-367 1   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-07-02   
443-367 2   9212 VERIZON MARYLAND, INC. 238      
443-367 3   9212 VERIZON MARYLAND, INC. 238      
443-367 4   829J PAETEC ITEL, LLC 238   2007-06-15   
443-367 5   9212 VERIZON MARYLAND, INC. 238      
443-367 6   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-03-28   
443-367 7   9212 VERIZON MARYLAND, INC. 238      
443-367 8   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-10-28   
443-367 9   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2011-04-03   
443-393 A   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-393 0   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-01-08   
443-393 1   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-01-08   
443-393 2   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-09-10   
443-393 3   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-09-10   
443-393 4   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-393 5   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-393 6   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-05-08   
443-393 7   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2011-04-03   
443-393 8   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-393 9   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-430 A BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-430 0   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-430 1   515J IP HORIZON LLC 238   2016-10-14   
443-430 2   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2005-08-14   
443-430 3   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-430 4   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2016-09-26   
443-430 5   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2016-09-26   
443-430 6   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2005-08-14   
443-430 7   7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2008-05-30   
443-430 8   7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2006-03-11   
443-430 9   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-472 A BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-472 0   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-06-03   
443-472 1   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2003-11-19   
443-472 2   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2003-11-03   
443-472 3   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-08-02   
443-472 4   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-472 5   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-11-04   
443-472 6   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2005-01-02   
443-472 7   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-02-28   
443-472 8   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2005-01-02   
443-472 9   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2005-11-01   
443-518 A CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
443-518 0   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2009-05-26   
443-518 1   9212 VERIZON MARYLAND, INC. 238   2009-03-02   
443-518 2   9212 VERIZON MARYLAND, INC. 238   2009-03-02   
443-518 3   9212 VERIZON MARYLAND, INC. 238   2009-03-02   
443-518 4   9212 VERIZON MARYLAND, INC. 238   2009-03-02   
443-518 5   9212 VERIZON MARYLAND, INC. 238   2009-03-02   
443-518 6   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2009-05-26   
443-518 7   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2010-04-08   
443-518 8   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2010-03-29   
443-518 9   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2009-06-23   
443-535 A CLVLMDCERP0  9212 VERIZON MARYLAND, INC. 238   2024-01-30   
443-535 0   9212 VERIZON MARYLAND, INC. 238      
443-535 1   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-05-20   
443-535 2   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-09-15   
443-535 3   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2006-01-21   
443-535 4   7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2006-05-15   
443-535 5   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2007-02-08   
443-535 6   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-03-21   
443-535 7   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2009-07-09   
443-535 8   9212 VERIZON MARYLAND, INC. 238      
443-535 9   9212 VERIZON MARYLAND, INC. 238      
443-537 A BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-537 0   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2009-10-30   
443-537 1   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2009-10-25   
443-537 2   829J PAETEC ITEL, LLC 238   2011-03-11   
443-537 3   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-06-03   
443-537 4   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2009-07-13   
443-537 5   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-06-14   
443-537 6   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-06-14   
443-537 7   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-06-14   
443-537 8   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-06-14   
443-537 9   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-02-05   
443-538 A BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-539 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-539 0   829J PAETEC ITEL, LLC 238      
443-539 1   829J PAETEC ITEL, LLC 238      
443-539 2   829J PAETEC ITEL, LLC 238      
443-539 3   829J PAETEC ITEL, LLC 238      
443-539 4   829J PAETEC ITEL, LLC 238   2006-08-15   
443-539 5   7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2008-10-01   
443-539 6   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-10-28   
443-539 7   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2010-02-15   
443-539 8   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2008-02-13   
443-539 9   829J PAETEC ITEL, LLC 238      
443-542 A BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238      
443-542 0   318J COMCAST IP PHONE, LLC 238      
443-542 1   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2004-11-25   
443-542 2   318J COMCAST IP PHONE, LLC 238      
443-542 3   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-03-12   
443-542 4   9212 VERIZON MARYLAND, INC. 238   2004-12-20   

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Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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