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Essex, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
443-231 A BLTMMDCHCMD  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-231 0 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-02-11   
443-231 1 PIVLMDPKXFX  829J PAETEC ITEL, LLC 238   2005-04-29   
443-231 2 BLTMMDCHCMD  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-231 3 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-04-24   
443-231 4 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2003-02-20   
443-231 5 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2005-03-10   
443-231 6 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2006-06-20   
443-231 7 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2006-06-20   
443-231 8 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2006-08-25   
443-231 9   515J IP HORIZON LLC 238   2016-05-31   
443-460 A BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-460 0 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-460 1 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-460 2 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-460 3 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-460 4 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-460 5 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-09-29   
443-460 6 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-460 7 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-460 8 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2008-03-31   
443-460 9 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-505 A BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-505 0 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-05-01   
443-505 1 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-05-01   
443-505 2 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2011-12-24   
443-505 3 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2014-03-20   
443-505 4 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-09-29   
443-505 5 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-01-26   
443-505 6 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2018-10-18   
443-505 7 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2008-05-16   
443-505 8 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2014-09-21   
443-505 9 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2019-10-07   
443-559 A BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238      
443-559 0 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238      
443-559 1 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2008-02-04   
443-559 2 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2007-03-02   
443-559 3   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   
443-559 4 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-04-29   
443-559 5 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2007-10-29   
443-559 6 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2007-10-29   
443-559 7 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2008-06-16   
443-559 8 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2008-06-16   
443-559 9 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2008-06-16   
443-579 A PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2025-04-01   
443-579 0 PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-579 1 PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-579 2 PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-579 3 PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-579 4 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-06-26   

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Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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