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Columbia, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
410-290 A CLMAMDOBDS0  9212 VERIZON MARYLAND, INC. 238      
410-309 A CLMAMDOBDS0  9212 VERIZON MARYLAND, INC. 238      
410-312 A CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
410-381 A CLMAMDOBDS0  9212 VERIZON MARYLAND, INC. 238      
410-423 A BLTMMDFMDS0  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
410-447 A HNVAMDAE3MD  6630 USA MOBILITY WIRELESS, INC. 238      
410-531 A CLVLMDCERP0  9212 VERIZON MARYLAND, INC. 238   2024-01-30   
410-707 A BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
410-715 A CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-730 A CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-740 A CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-772 A CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-772 0 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-772 1 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-772 2 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-772 3 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-772 4 BLTMMDCH40Z  5562 METROPCS, INC. 238   2015-07-03   
410-772 5 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-772 6 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-772 7 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-772 8 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-772 9 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-794 A BLTMMDDNDS2  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238      
410-794 0 BLTMMDDNDS2  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238      
410-794 1 BLTMMDDNDS2  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238      
410-794 2 BLTMMDDNDS2  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238      
410-794 3 BLTMMDDNDS2  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238      
410-794 4 BLTMMDDNDS2  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238      
410-794 5 BLTMMDCH25Z  8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 238   2006-05-04   
410-794 6 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2007-06-01   
410-794 7 BLTMMDDNDS2  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238      
410-794 8 BLTMMDDNDS2  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238      
410-794 9 BLTMMDDNDS2  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238      
410-872 A CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
410-884 A CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-910 A BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238      
410-953 A CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
410-953 0 CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
410-953 1 CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
410-953 2 CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
410-953 3 CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
410-953 4 CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
410-953 5 CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
410-953 6 CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
410-953 7 CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
410-953 8 CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
410-953 9 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2010-09-24   
410-964 A CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-992 A CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-992 0 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-992 1 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-992 2 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-10-28   
410-992 3 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-992 4 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-992 5 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-992 6 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-992 7 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-992 8 ELCYMDELDS0  9212 VERIZON MARYLAND, INC. 238      
410-992 9 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
410-997 A CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
443-259 A CLMAMDOBDS0  9212 VERIZON MARYLAND, INC. 238      
443-259 0 CLMAMDOBDS0  9212 VERIZON MARYLAND, INC. 238      
443-259 1 CLMAMDOBDS0  9212 VERIZON MARYLAND, INC. 238      
443-259 2 CLMAMDOBDS0  9212 VERIZON MARYLAND, INC. 238      
443-259 3 CLMAMDOBDS0  9212 VERIZON MARYLAND, INC. 238      
443-259 4 CLMAMDOBDS0  9212 VERIZON MARYLAND, INC. 238      
443-259 5   829J PAETEC ITEL, LLC 238   2013-09-05   
443-259 6 CLMAMDOBDS0  9212 VERIZON MARYLAND, INC. 238      
443-259 7 CLMAMDOBDS0  9212 VERIZON MARYLAND, INC. 238      
443-259 8 CLMAMDOBDS0  9212 VERIZON MARYLAND, INC. 238      
443-259 9   829J PAETEC ITEL, LLC 238   2003-02-25   
443-276 A BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-276 0 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-276 1 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-276 2 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-276 3 BLTMMDCH08Z  4492 VDL, INC. DBA GLOBAL TELECOM BROKERS - MD 238   2003-11-08   
443-276 4 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-276 5 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-276 6 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-276 7 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-276 8   2593 CORE COMMUNICATIONS, INC.- MD 238   2004-03-29   
443-276 9 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-283 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-285 A CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
443-285 0 CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
443-285 1 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-04-20   
443-285 2 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-09-29   
443-285 3 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-08-19   
443-285 4 CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
443-285 5 CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
443-285 6 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-285 7 CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
443-285 8 CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238      
443-285 9 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2004-09-29   
443-319 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-319 0   829J PAETEC ITEL, LLC 238      
443-319 1 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2020-08-13   
443-319 2 BLTMMDCH40Z  5562 METROPCS, INC. 238   2016-01-08   
443-319 3 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2008-06-16   
443-319 4   829J PAETEC ITEL, LLC 238   2005-07-04   

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

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