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Dundalk, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
410-282 A DNDLMDDNDS0  9212 VERIZON MARYLAND, INC. 238      
410-284 A DNDLMDDNDS0  9212 VERIZON MARYLAND, INC. 238      
410-285 A DNDLMDDNDS0  9212 VERIZON MARYLAND, INC. 238      
410-288 A DNDLMDDNDS0  9212 VERIZON MARYLAND, INC. 238      
410-650 A BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
410-650 0   876D ONVOY, LLC - MD 238   2016-03-31   
410-650 1   8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 238   2015-06-11   
410-650 2   7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238      
410-650 3   4492 VDL, INC. DBA GLOBAL TELECOM BROKERS - MD 238   2003-11-08   
410-650 4   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-05-08   
410-650 5   071F BANDWIDTH.COM CLEC, LLC - MD 238   2004-11-27   
410-650 6   876D ONVOY, LLC - MD 238   2016-03-10   
410-650 7   7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238   2006-06-01   
410-650 8   876D ONVOY, LLC - MD 238   2016-03-31   
410-650 9   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-216 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-216 0   2593 CORE COMMUNICATIONS, INC.- MD 238   2004-03-29   
443-216 1   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-06-26   
443-216 2   829J PAETEC ITEL, LLC 238   2001-11-02   
443-216 3   829J PAETEC ITEL, LLC 238   2001-11-02   
443-216 4   829J PAETEC ITEL, LLC 238   2001-11-02   
443-216 5   829J PAETEC ITEL, LLC 238   2001-11-02   
443-216 6   829J PAETEC ITEL, LLC 238   2001-11-02   
443-216 7   318J COMCAST IP PHONE, LLC 238   2005-03-10   
443-216 8   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2019-07-13   
443-216 9   071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-06-26   
443-376 A BLTMMDFMDS0  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-376 0   7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-376 1   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   
443-376 2   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-03-28   
443-376 3   829J PAETEC ITEL, LLC 238   2007-06-14   
443-376 4   318J COMCAST IP PHONE, LLC 238   2019-05-10   
443-376 5   318J COMCAST IP PHONE, LLC 238   2007-08-13   
443-376 6   071F BANDWIDTH.COM CLEC, LLC - MD 238   2019-03-16   
443-376 7   071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-11-28   
443-376 8   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-07-02   
443-376 9   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   
443-399 A   876D ONVOY, LLC - MD 238      
443-399 0   876D ONVOY, LLC - MD 238   2024-10-21   
443-399 1   876D ONVOY, LLC - MD 238   2024-10-21   
443-399 2   876D ONVOY, LLC - MD 238   2012-10-08   
443-399 3   071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-05-23   
443-399 5   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2020-10-28   
443-399 6   071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-05-23   
443-399 7   508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-04-02   
443-399 8   318J COMCAST IP PHONE, LLC 238   2008-03-19   
443-399 9   515J IP HORIZON LLC 238   2013-09-06   
443-407 A BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-407 0   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-407 1   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      

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

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