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Columbia, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
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 PIVLMDPKXEX  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 PIVLMDPKXEX  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 PIVLMDPKXEX  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 PIVLMDPKXHX  829J PAETEC ITEL, LLC 238   2025-04-01   
443-319 0 PIVLMDPKXHX  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 PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2005-07-04   

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Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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