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Washington Zone 14 (Baltimore LATA), MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
240-509 A BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238      
240-509 0   071F BANDWIDTH.COM CLEC, LLC - MD 238   2014-06-06   
240-509 1   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-05   
240-509 2   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
240-509 3   7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2008-10-01   
240-509 4   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
240-509 5   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
240-509 6   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2019-12-28   
240-509 7   508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-25   
240-509 8   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-05   
240-509 9   071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-01-02   
240-742 A BLTMMDCHXKX  478J NUSO, LLC 238      
240-742 0   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2023-10-20   
240-742 1   478J NUSO, LLC 238   2021-01-21   
240-742 2   876D ONVOY, LLC - MD 238   2021-03-04   
240-742 3   876D ONVOY, LLC - MD 238   2021-07-12   
240-742 4   876D ONVOY, LLC - MD 238   2022-10-16   
240-742 5   624H ONVOY SPECTRUM, LLC 238   2022-03-03   
240-742 6   624H ONVOY SPECTRUM, LLC 238   2021-05-23   
240-742 7   7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238   2024-12-23   
240-742 8   624H ONVOY SPECTRUM, LLC 238   2022-03-03   
240-742 9   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2021-12-02   
240-842 A BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
240-842 0   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
240-842 1   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
240-842 2   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   
240-842 3   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-12-09   
240-842 4   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   
240-842 5   2593 CORE COMMUNICATIONS, INC.- MD 238   2012-08-26   
240-842 6   829J PAETEC ITEL, LLC 238   2016-11-21   
240-842 7   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   
240-842 8   073H TELNYX LLC 238   2017-04-26   
240-842 9   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
240-865 A BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
240-865 0   318J COMCAST IP PHONE, LLC 238   2008-02-01   
240-865 1   829J PAETEC ITEL, LLC 238   2006-01-14   
240-865 2   2593 CORE COMMUNICATIONS, INC.- MD 238   2008-04-07   
240-865 3   876D ONVOY, LLC - MD 238   2012-09-06   
240-865 4   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-08-11   
240-865 5   829J PAETEC ITEL, LLC 238   2007-03-02   
240-865 6   145J TERRA NOVA TELECOM INC. 238   2023-08-06   
240-865 7   829J PAETEC ITEL, LLC 238   2007-09-20   
240-865 8   7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2007-12-03   
240-865 9   8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 238   2006-05-05   
301-205 A MAYOMDMYRS1  9212 VERIZON MARYLAND, INC. 238      
301-205 0   9212 VERIZON MARYLAND, INC. 238      
301-205 1   321J HD CARRIER LLC 238   2016-05-14   
301-205 2   321J HD CARRIER LLC 238   2016-05-14   
301-205 3   321J HD CARRIER LLC 238   2016-05-14   
301-205 4   321J HD CARRIER LLC 238   2016-05-14   
301-205 5   876D ONVOY, LLC - MD 238   2020-10-17   
301-205 6   321J HD CARRIER LLC 238   2016-05-14   
301-205 7   321J HD CARRIER LLC 238   2016-05-14   
301-205 8   321J HD CARRIER LLC 238   2016-05-14   
301-205 9   321J HD CARRIER LLC 238   2016-05-14   
301-261 A COTNMDCRDS0  9212 VERIZON MARYLAND, INC. 238      
301-612 A BLTMMDCHCMD  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
301-612 0   321J HD CARRIER LLC 238   2016-09-05   
301-612 1   321J HD CARRIER LLC 238   2016-09-05   
301-612 2   321J HD CARRIER LLC 238   2016-05-14   
301-612 3   321J HD CARRIER LLC 238   2016-09-05   
301-612 4   321J HD CARRIER LLC 238   2016-09-05   
301-612 5   321J HD CARRIER LLC 238   2016-09-05   
301-612 6   7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238   2012-12-09   
301-612 7   321J HD CARRIER LLC 238   2016-09-05   
301-612 8   321J HD CARRIER LLC 238   2016-09-05   
301-612 9   321J HD CARRIER LLC 238   2016-09-05   
301-621 A ODTNMDONDS0  9212 VERIZON MARYLAND, INC. 238      
301-629 A CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
301-629 0   9212 VERIZON MARYLAND, INC. 238      
301-629 1   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-24   
301-629 2   9212 VERIZON MARYLAND, INC. 238      
301-629 3   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-24   
301-629 4   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-24   
301-629 5   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-24   
301-629 6   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   
301-629 7   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   
301-629 8   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-24   
301-629 9   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   
301-858 A COTNMDCRDS0  9212 VERIZON MARYLAND, INC. 238      
301-889 A GLVLMDGLRS1  9212 VERIZON MARYLAND, INC. 238      
301-889 0   9212 VERIZON MARYLAND, INC. 238      
301-889 1   321J HD CARRIER LLC 238   2016-09-05   
301-889 2   624H ONVOY SPECTRUM, LLC 238   2021-11-08   
301-889 3   321J HD CARRIER LLC 238   2016-09-05   
301-889 4   321J HD CARRIER LLC 238   2016-09-05   
301-889 5   321J HD CARRIER LLC 238   2016-09-05   
301-889 6   321J HD CARRIER LLC 238   2016-09-05   
301-889 7   321J HD CARRIER LLC 238   2016-09-05   
301-889 8   876D ONVOY, LLC - MD 238   2016-04-07   
301-889 9   876D ONVOY, LLC - MD 238   2016-04-07   
301-912 A ODTNMDONDS0  9212 VERIZON MARYLAND, INC. 238      
301-912 0   9212 VERIZON MARYLAND, INC. 238      
301-912 1   9212 VERIZON MARYLAND, INC. 238      
301-912 2   9212 VERIZON MARYLAND, INC. 238      
301-912 3   9212 VERIZON MARYLAND, INC. 238      
301-912 4   9212 VERIZON MARYLAND, INC. 238      
301-912 5   9212 VERIZON MARYLAND, INC. 238      
301-912 6   9212 VERIZON MARYLAND, INC. 238      
301-912 7   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      

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

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