Local Calling Guide

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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 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2014-06-06   
240-509 1 BLTQMD01DS0  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 BLTOMDKHDS0  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 BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2019-12-28   
240-509 7 BLTMMDDN2MD  508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-25   
240-509 8 BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-05   
240-509 9 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-01-02   
240-742 A BLTMMDCHXKX  478J NUSO, LLC 238      
240-742 0 BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2023-10-20   
240-742 1 BLTMMDCHXKX  478J NUSO, LLC 238   2021-01-21   
240-742 2 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-03-04   
240-742 3 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-07-12   
240-742 4 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2022-10-16   
240-742 5 BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2022-03-03   
240-742 6 BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2021-05-23   
240-742 7 BLTMMDCHCMD  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238   2024-12-23   
240-742 8 BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2022-03-03   
240-742 9 BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2021-12-02   
240-842 A BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
240-842 0 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
240-842 1 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
240-842 2   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   
240-842 3 BLTMMDCH45Z  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 BLTMMDCHX7X  073H TELNYX LLC 238   2017-04-26   
240-842 9 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
240-865 A BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
240-865 0 BLTMMDCHXFX  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 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2012-09-06   
240-865 4 BLTMMDSN6MD  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 BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2007-12-03   
240-865 9 BLTMMDCH25Z  8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 238   2006-05-05   
301-205 A MAYOMDMYRS1  9212 VERIZON MARYLAND, INC. 238      
301-205 0 MAYOMDMYRS1  9212 VERIZON MARYLAND, INC. 238      
301-205 1 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-05-14   
301-205 2 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-05-14   
301-205 3 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-05-14   
301-205 4 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-05-14   
301-205 5 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2020-10-17   
301-205 6 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-05-14   
301-205 7 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-05-14   
301-205 8 BLTMMDCHXVX  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 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-09-05   
301-612 1 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-09-05   
301-612 2 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-05-14   
301-612 3 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-09-05   
301-612 4 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-09-05   
301-612 5 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-09-05   
301-612 6 BLTMMDCHCMD  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238   2012-12-09   
301-612 7 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-09-05   
301-612 8 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-09-05   
301-612 9 BLTMMDCHXVX  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 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
301-629 1   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-24   
301-629 2 CLMAMDCBRP0  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 GLVLMDGLRS1  9212 VERIZON MARYLAND, INC. 238      
301-889 1 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-09-05   
301-889 2 BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2021-11-08   
301-889 3 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-09-05   
301-889 4 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-09-05   
301-889 5 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-09-05   
301-889 6 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-09-05   
301-889 7 BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-09-05   
301-889 8 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-04-07   
301-889 9 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-04-07   
301-912 A ODTNMDONDS0  9212 VERIZON MARYLAND, INC. 238      
301-912 0 ODTNMDONDS0  9212 VERIZON MARYLAND, INC. 238      
301-912 1 ODTNMDONDS0  9212 VERIZON MARYLAND, INC. 238      
301-912 2 ODTNMDONDS0  9212 VERIZON MARYLAND, INC. 238      
301-912 3 ODTNMDPORS2  9212 VERIZON MARYLAND, INC. 238      
301-912 4 ODTNMDONDS0  9212 VERIZON MARYLAND, INC. 238      
301-912 5 ODTNMDPORS2  9212 VERIZON MARYLAND, INC. 238      
301-912 6 ODTNMDONDS0  9212 VERIZON MARYLAND, INC. 238      
301-912 7 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      

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Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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