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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      
443-574 1   829J PAETEC ITEL, LLC 238      
443-574 2   829J PAETEC ITEL, LLC 238      
443-574 3   829J PAETEC ITEL, LLC 238      
443-574 4   071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-10-28   
443-574 5   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-02-26   
443-574 6   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-08-19   
443-574 7   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-08-28   
443-574 8   829J PAETEC ITEL, LLC 238   2003-05-25   
443-574 9   829J PAETEC ITEL, LLC 238      
443-638 A BLTMMDDN4MD  2554 GLOBAL NAPS SOUTH, INC. - MD 238      
443-828 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-828 0   829J PAETEC ITEL, LLC 238      
443-828 1   829J PAETEC ITEL, LLC 238      
443-828 2   515J IP HORIZON LLC 238   2013-09-06   
443-828 3   829J PAETEC ITEL, LLC 238      
443-828 4   829J PAETEC ITEL, LLC 238      
443-828 5   829J PAETEC ITEL, LLC 238      
443-828 6   829J PAETEC ITEL, LLC 238      
443-828 7   508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-25   
443-828 8   829J PAETEC ITEL, LLC 238      
443-828 9   829J PAETEC ITEL, LLC 238      
443-973 A BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-973 0   071F BANDWIDTH.COM CLEC, LLC - MD 238   2024-10-26   
443-973 1   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2019-10-18   
443-973 2   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-03-21   
443-973 3   7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2008-10-01   
443-973 4   876D ONVOY, LLC - MD 238   2014-09-05   
443-973 5   876D ONVOY, LLC - MD 238   2014-10-17   
443-973 6   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-06-02   
443-973 7   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-973 8   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-973 9   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2001-11-19   
667-280 A BLTMMDCHXQX  197D VONAGE AMERICA LLC 238      
667-280 0   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2021-03-12   
667-280 1   624H ONVOY SPECTRUM, LLC 238   2021-11-20   
667-280 3   197D VONAGE AMERICA LLC 238   2020-06-19   
667-280 4   876D ONVOY, LLC - MD 238   2021-03-04   
667-280 5   876D ONVOY, LLC - MD 238   2021-03-04   
667-280 6   876D ONVOY, LLC - MD 238   2021-03-04   
667-280 7   197D VONAGE AMERICA LLC 238   2020-06-19   
667-280 8   624H ONVOY SPECTRUM, LLC 238   2021-05-22   
667-280 9   876D ONVOY, LLC - MD 238   2021-09-23   
667-371 A   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
667-371 0   071F BANDWIDTH.COM CLEC, LLC - MD 238   2022-09-30   
667-371 1   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2023-03-10   
667-371 2   876D ONVOY, LLC - MD 238   2023-08-10   
667-371 3   624H ONVOY SPECTRUM, LLC 238   2022-03-21   
667-371 4   624H ONVOY SPECTRUM, LLC 238   2022-03-21   
667-371 5   876D ONVOY, LLC - MD 238   2023-08-10   
667-371 6   624H ONVOY SPECTRUM, LLC 238   2022-02-07   

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Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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