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Dundalk, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
443-407 2   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-407 3   624H ONVOY SPECTRUM, LLC 238   2022-03-24   
443-407 4   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-407 5   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-407 6   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-407 7   071F BANDWIDTH.COM CLEC, LLC - MD 238   2019-03-16   
443-407 8   876D ONVOY, LLC - MD 238   2016-03-31   
443-407 9   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-503 A BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-503 0   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-503 1   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-503 2   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-503 3   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-02-11   
443-503 4   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2003-02-20   
443-503 5   318J COMCAST IP PHONE, LLC 238   2006-09-18   
443-503 6   318J COMCAST IP PHONE, LLC 238   2006-09-18   
443-503 7   829J PAETEC ITEL, LLC 238   2009-04-20   
443-503 8   318J COMCAST IP PHONE, LLC 238   2013-02-04   
443-503 9   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2020-03-17   
443-530 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-530 0   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-530 1   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-530 2   515J IP HORIZON LLC 238   2016-10-14   
443-530 3   318J COMCAST IP PHONE, LLC 238   2014-02-14   
443-530 4   071F BANDWIDTH.COM CLEC, LLC - MD 238   2017-10-01   
443-530 5   876D ONVOY, LLC - MD 238   2016-01-22   
443-530 6   318J COMCAST IP PHONE, LLC 238   2016-04-28   
443-530 7   071F BANDWIDTH.COM CLEC, LLC - MD 238   2018-05-28   
443-530 8   073H TELNYX LLC 238   2017-04-25   
443-530 9   829J PAETEC ITEL, LLC 238      
443-549 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-549 0   829J PAETEC ITEL, LLC 238      
443-549 1   829J PAETEC ITEL, LLC 238      
443-549 2   829J PAETEC ITEL, LLC 238      
443-549 3   829J PAETEC ITEL, LLC 238      
443-549 4   318J COMCAST IP PHONE, LLC 238   2015-05-13   
443-549 5   964H BARR TELL USA, INC. 238   2016-12-17   
443-549 6   145J TERRA NOVA TELECOM INC. 238   2024-02-15   
443-549 7   071F BANDWIDTH.COM CLEC, LLC - MD 238   2024-11-03   
443-549 8   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
443-549 9   829J PAETEC ITEL, LLC 238      
443-586 A BLTMMD91GT0  2593 CORE COMMUNICATIONS, INC.- MD 238      
443-586 0   876D ONVOY, LLC - MD 238   2024-02-29   
443-586 1   876D ONVOY, LLC - MD 238   2024-02-29   
443-586 2   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-22   
443-586 3   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-22   
443-586 4   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-22   
443-586 5   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2017-11-24   
443-586 6   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2017-11-24   
443-586 7   876D ONVOY, LLC - MD 238   2024-02-29   

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

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