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Ellicott City, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
443-288 3   281E YMAX COMMUNICATIONS CORP. - MD 238   2009-10-24   
443-288 4   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-288 5   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-288 6   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-288 7   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-288 8   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-288 9   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-325 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-325 0   829J PAETEC ITEL, LLC 238      
443-325 1   829J PAETEC ITEL, LLC 238      
443-325 2   5562 METROPCS, INC. 238   2013-06-14   
443-325 3   5562 METROPCS, INC. 238   2013-06-14   
443-325 4   5562 METROPCS, INC. 238   2015-02-01   
443-325 5   318J COMCAST IP PHONE, LLC 238   2014-01-06   
443-325 6   5562 METROPCS, INC. 238   2016-02-04   
443-325 7   829J PAETEC ITEL, LLC 238      
443-325 8   829J PAETEC ITEL, LLC 238      
443-325 9   829J PAETEC ITEL, LLC 238      
443-355 A BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-355 0   073H TELNYX LLC 238   2017-03-14   
443-355 1   5562 METROPCS, INC. 238   2017-01-19   
443-355 2   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
443-355 3   5562 METROPCS, INC. 238   2017-01-19   
443-355 4   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-355 5   5562 METROPCS, INC. 238   2017-03-25   
443-355 6   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2017-05-29   
443-355 7   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2017-05-29   
443-355 8   5562 METROPCS, INC. 238   2017-10-14   
443-355 9   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2017-10-20   
443-364 A CLMAMDNIDS1  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-364 0   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2018-08-27   
443-364 1   5562 METROPCS, INC. 238   2018-04-29   
443-364 2   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2007-05-23   
443-364 3   876D ONVOY, LLC - MD 238   2012-02-29   
443-364 4   281E YMAX COMMUNICATIONS CORP. - MD 238   2008-07-26   
443-364 5   7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-364 6   281E YMAX COMMUNICATIONS CORP. - MD 238   2009-02-11   
443-364 7   281E YMAX COMMUNICATIONS CORP. - MD 238   2009-02-11   
443-364 8   071F BANDWIDTH.COM CLEC, LLC - MD 238   2008-12-11   
443-364 9   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2007-07-27   
443-420 A   071F BANDWIDTH.COM CLEC, LLC - MD 238      
443-420 2   5562 METROPCS, INC. 238   2018-10-05   
443-420 3   318J COMCAST IP PHONE, LLC 238   2019-03-20   
443-420 5   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2025-08-15   
443-420 6   876D ONVOY, LLC - MD 238   2016-04-08   
443-420 7   071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-02-22   
443-420 8   071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-02-22   
443-420 9   876D ONVOY, LLC - MD 238   2016-04-08   
443-574 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-574 0   829J PAETEC ITEL, LLC 238      

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

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