Local Calling Guide

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Baltimore, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
443-965 1 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2023-10-20   
443-965 2 BLTMMDCHDS2  9212 VERIZON MARYLAND, INC. 238   2006-08-31   
443-965 3 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2023-10-20   
443-965 4 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2023-10-20   
443-965 5 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2023-10-20   
443-965 6 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2023-10-20   
443-965 7 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-12-31   
443-965 8 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2006-08-23   
443-965 9 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2010-08-09   
443-970 A BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-970 0 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2012-01-19   
443-970 1 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2012-01-19   
443-970 2 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2012-01-19   
443-970 3 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2012-01-19   
443-970 4 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2012-01-19   
443-970 5 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2012-01-20   
443-970 6 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2012-01-20   
443-970 7 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2012-01-22   
443-970 8 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2012-01-22   
443-970 9 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2012-01-22   
443-977 A BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-977 0 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2006-12-07   
443-977 1 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2007-10-22   
443-977 2 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2007-10-22   
443-977 3 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2007-10-22   
443-977 4 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-12-08   
443-977 5 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2007-10-22   
443-977 6 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-12-08   
443-977 7 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2007-01-02   
443-977 8 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2007-03-05   
443-977 9 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2007-03-05   
443-982 A BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238      
443-982 0 BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2007-07-14   
443-982 1 BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2007-07-14   
443-982 2 BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2007-07-14   
443-982 3 BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2007-07-14   
443-982 4 BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2007-07-14   
443-982 5 BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2007-07-14   
443-982 6 BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2007-07-14   
443-982 7 BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2007-07-14   
443-982 8 BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2007-07-14   
443-982 9 BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2007-07-14   
443-983 A BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-983 0   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-983 1   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-983 2   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-983 3   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-983 4   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-983 5   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-983 6   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      

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

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