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Crofton, MD

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
410-451 A COTNMDCRDS0  9212 VERIZON MARYLAND, INC. 238      
410-721 A COTNMDCRDS0  9212 VERIZON MARYLAND, INC. 238      
410-774 A BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238      
410-774 0 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-03-25   
410-774 1 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-03-25   
410-774 2 BLTMMDCH08Z  4492 VDL, INC. DBA GLOBAL TELECOM BROKERS - MD 238   2004-02-14   
410-774 3   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   
410-774 4 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2003-08-20   
410-774 5 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-02-11   
410-774 6 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-02-22   
410-774 7 COTNMDCRDS0  9212 VERIZON MARYLAND, INC. 238   2005-10-15   
410-774 8   829J PAETEC ITEL, LLC 238   2003-02-25   
410-774 9 BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238      
443-292 A BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-292 0   2593 CORE COMMUNICATIONS, INC.- MD 238   2004-03-29   
443-292 1 BLTMMDFMDS0  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238   2006-07-31   
443-292 2 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-10-14   
443-292 3   829J PAETEC ITEL, LLC 238   2007-10-03   
443-292 4 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2005-03-10   
443-292 5 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2008-01-25   
443-292 6 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-09-04   
443-292 7   829J PAETEC ITEL, LLC 238   2010-10-22   
443-292 8 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2006-12-29   
443-292 9 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2012-06-15   
443-302 A   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-302 0 BLTQMD018MD  145J TERRA NOVA TELECOM INC. 238   2024-10-12   
443-302 2 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2008-03-20   
443-302 3 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-05-21   
443-302 6 BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2008-10-01   
443-302 7 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2008-02-12   
443-302 8 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-05-21   
443-302 9 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2008-12-11   
443-332 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-332 0   829J PAETEC ITEL, LLC 238      
443-332 1 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2020-09-12   
443-332 2 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2021-08-30   
443-332 3 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-03-03   
443-332 4   829J PAETEC ITEL, LLC 238   2002-07-12   
443-332 5 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2021-08-30   
443-332 6   829J PAETEC ITEL, LLC 238   2006-03-28   
443-332 7 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-04-29   
443-332 8 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2020-11-29   
443-332 9 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-04-29   
443-584 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-584 0 BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2021-05-22   
443-584 1   829J PAETEC ITEL, LLC 238      
443-584 2 BLTQMD018MD  145J TERRA NOVA TELECOM INC. 238   2024-02-15   
443-584 3 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2014-06-06   
443-584 4 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2014-07-20   
443-584 5 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-05-21   
443-584 6 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-05-21   
443-584 7 BLTMMDDN2MD  508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-25   
443-584 8   515J IP HORIZON LLC 238   2016-10-14   
443-584 9   515J IP HORIZON LLC 238   2015-03-21   
667-295 A BLTMMD91GT0  2593 CORE COMMUNICATIONS, INC.- MD 238      
667-295 0   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-12-06   
667-295 1   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-12-06   
667-295 2 BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2018-12-07   
667-295 3 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2023-08-10   
667-295 4 BLTMMD91GT0  2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-02   
667-295 5 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2020-11-29   
667-295 6 BLTMMD91GT0  2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-02   
667-295 7 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2019-02-19   
667-295 8 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2019-02-19   
667-295 9   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-12-06   
667-307 A BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238      
667-307 0 BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-06-08   
667-307 1 BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-06-08   
667-307 2 BLTMMDCHX7X  073H TELNYX LLC 238   2017-04-26   
667-307 3 BLTQMD012MD  964H BARR TELL USA, INC. 238   2016-12-17   
667-307 4 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2013-11-15   
667-307 5   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
667-307 6 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-03-03   
667-307 7 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-03-23   
667-307 8 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-03-23   
667-307 9   515J IP HORIZON LLC 238   2016-01-04   
667-338 A BLTMMDCH42Z  876D ONVOY, LLC - MD 238      
667-338 0 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2022-01-27   
667-338 1 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2022-01-27   
667-338 2 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-10-31   
667-338 3 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-10-31   
667-338 4 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-10-31   
667-338 5 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2022-11-28   
667-338 6 BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2022-02-12   
667-338 7 BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2022-02-12   
667-338 8 BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2021-11-01   
667-338 9 BLTMMDCHXQX  197D VONAGE AMERICA LLC 238   2022-10-07   
667-475 A BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-05-12   
667-475 0 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-05-12   
667-475 9 BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2024-12-19   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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