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Cockeysville, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
443-353 1 CYVLMDDADS0  9212 VERIZON MARYLAND, INC. 238   2004-05-05   
443-353 2 CYVLMDDADS0  9212 VERIZON MARYLAND, INC. 238   2004-05-05   
443-353 3 CYVLMDDADS0  9212 VERIZON MARYLAND, INC. 238   2004-05-05   
443-353 4 BLTMMDDNDS2  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238   2012-04-26   
443-353 5 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2015-04-10   
443-353 6   829J PAETEC ITEL, LLC 238   2008-06-09   
443-353 7 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-06-04   
443-353 8   515J IP HORIZON LLC 238   2016-01-04   
443-353 9 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2008-12-11   
443-391 A   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2025-04-04   
443-391 2 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2013-05-01   
443-391 3 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2013-05-15   
443-391 5 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-391 6 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2013-06-01   
443-391 7 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2016-08-21   
443-391 8 BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-391 9 BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-428 A BLTMMD91GT0  2593 CORE COMMUNICATIONS, INC.- MD 238      
443-541 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-541 0   829J PAETEC ITEL, LLC 238      
443-541 1   829J PAETEC ITEL, LLC 238      
443-541 2   829J PAETEC ITEL, LLC 238      
443-541 3   829J PAETEC ITEL, LLC 238      
443-541 4 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2003-08-20   
443-541 5 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-01-10   
443-541 6   515J IP HORIZON LLC 238   2016-10-14   
443-541 7 BLTMMDCHX7X  073H TELNYX LLC 238   2017-03-14   
443-541 8   829J PAETEC ITEL, LLC 238      
443-541 9   829J PAETEC ITEL, LLC 238      
443-556 A CYVLMDDADS0  9212 VERIZON MARYLAND, INC. 238      
443-578 A BLTMMDSNDS5  4773 XO MARYLAND, LLC 238      
443-578 0 BLTMMDSNDS5  4773 XO MARYLAND, LLC 238      
443-578 1 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2014-10-21   
443-578 2 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2015-10-26   
443-578 3 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2012-02-27   
443-578 4 BLTMMDSNDS5  4773 XO MARYLAND, LLC 238      
443-578 5 BLTMMDSNDS5  4773 XO MARYLAND, LLC 238      
443-578 6 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2013-08-15   
443-578 7 BLTMMDDN2MD  508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-25   
443-578 8   829J PAETEC ITEL, LLC 238   2008-09-26   
443-578 9   515J IP HORIZON LLC 238   2015-03-23   
443-589 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-589 0   829J PAETEC ITEL, LLC 238      
443-589 1   829J PAETEC ITEL, LLC 238      
443-589 2   829J PAETEC ITEL, LLC 238      
443-589 3   829J PAETEC ITEL, LLC 238      
443-589 4 BLTMMDCH40Z  5562 METROPCS, INC. 238   2013-06-14   
443-589 5 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2018-10-19   
443-589 6 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-07-15   
443-589 7 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-03-14   

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Last updated: Wed, 04 Mar 2026 03:00:52 UTC

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