Local Calling Guide

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Baltimore, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
443-836 A BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-836 0 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-836 1 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-08-26   
443-836 2   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-12   
443-836 3   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-12   
443-836 4 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2018-12-13   
443-836 5 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2020-02-13   
443-836 6 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2017-12-05   
443-836 7 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2017-12-05   
443-836 8   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-19   
443-836 9   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-19   
443-838 A CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
443-839 A BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-839 0 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-01-27   
443-839 1 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-08-26   
443-839 2 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2006-07-09   
443-839 3 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2006-07-09   
443-839 4 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2006-06-08   
443-839 5 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2006-06-08   
443-839 6 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2006-06-08   
443-839 7 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2006-06-08   
443-839 8 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2008-04-08   
443-839 9 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2006-06-08   
443-842 A BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-842 0 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-05-06   
443-842 1 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-05-09   
443-842 2 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-05-09   
443-842 3 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-05-09   
443-842 4 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-05-20   
443-842 5 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-05-20   
443-842 6 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-05-20   
443-842 7 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2011-06-05   
443-842 8 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2012-01-22   
443-842 9 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2012-01-22   
443-844 A BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-844 0 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2006-04-07   
443-844 1 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2006-04-07   
443-844 2 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2006-04-10   
443-844 3 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-04-10   
443-844 4 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2006-04-10   
443-844 5 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2006-04-10   
443-844 6 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2006-04-10   
443-844 7 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2006-04-10   
443-844 8 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2006-04-10   
443-844 9 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2006-04-24   
443-845 A BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-845 0 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-845 1 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-845 2 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-845 3 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2005-06-02   

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Last updated: Tue, 29 Sep 2026 03:00:13 UTC

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