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Cockeysville, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
410-773 6 BLTMMDFMDS0  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
410-773 7 CYVLMDDADS0  9212 VERIZON MARYLAND, INC. 238      
410-773 8 CYVLMDDADS0  9212 VERIZON MARYLAND, INC. 238      
410-773 9 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-05-08   
410-785 A CYVLMDDADS0  9212 VERIZON MARYLAND, INC. 238      
410-891 A BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238      
410-891 0 BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238      
410-891 1 BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238      
410-891 2 BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238      
410-891 3 BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238      
410-891 4 BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2010-02-25   
410-891 5 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2003-02-18   
410-891 6 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-03-31   
410-891 7 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-06-07   
410-891 8 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2008-04-10   
410-891 9 BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238      
443-281 A BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-281 0 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-281 1 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-281 2 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-281 3 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-10-21   
443-281 5 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-281 6 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-281 7 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-281 8 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2007-08-08   
443-281 9 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2017-07-31   
443-318 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-318 0   829J PAETEC ITEL, LLC 238      
443-318 1 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2020-09-04   
443-318 2 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2020-07-10   
443-318 3 BLTMMDCH40Z  5562 METROPCS, INC. 238   2015-07-03   
443-318 4 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2005-03-10   
443-318 5 BLTMMDCH40Z  5562 METROPCS, INC. 238   2017-01-18   
443-318 6 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2020-09-28   
443-318 7 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2007-12-04   
443-318 8 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-10-14   
443-318 9   829J PAETEC ITEL, LLC 238      
443-330 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-330 0   829J PAETEC ITEL, LLC 238      
443-330 1   829J PAETEC ITEL, LLC 238      
443-330 2 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-02-22   
443-330 3   829J PAETEC ITEL, LLC 238   2005-03-10   
443-330 4   829J PAETEC ITEL, LLC 238   2004-09-05   
443-330 5 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2006-10-22   
443-330 6 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2011-04-13   
443-330 7 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2013-09-08   
443-330 8 MANRMDMNRS0  9212 VERIZON MARYLAND, INC. 238   2006-10-16   
443-330 9   829J PAETEC ITEL, LLC 238      
443-353 A CYVLMDDADS0  9212 VERIZON MARYLAND, INC. 238      
443-353 0 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2014-10-26   

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Last updated: Wed, 04 Mar 2026 03:00:52 UTC

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