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Crofton, MD

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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   

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Last updated: Sun, 17 May 2026 03:26:51 UTC

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