Local Calling Guide

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Baltimore, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
443-301 9 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2012-06-07   
443-310 A CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
443-314 A BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-314 0 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-03-18   
443-314 1 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-03-18   
443-314 2 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-03-18   
443-314 3 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-03-18   
443-314 4 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-03-18   
443-314 5 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-03-18   
443-314 6 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-03-18   
443-314 7 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-03-18   
443-314 8 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-03-18   
443-314 9 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-03-18   
443-320 A BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-320 0 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-320 1 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-320 2 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-320 3 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2004-12-03   
443-320 4 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-320 5 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-320 6 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-01-06   
443-320 7 PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2012-03-13   
443-320 8 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-01-06   
443-320 9 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-324 A BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-324 0 BLTMMDCH40Z  5562 METROPCS, INC. 238      
443-324 1 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-324 2 BLTMMDCH40Z  5562 METROPCS, INC. 238      
443-324 3 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-324 4 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-324 5 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-324 6 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-324 7 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-324 8 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-324 9 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-326 A CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
443-378 A BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2024-02-09   
443-378 0 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-07-25   
443-378 1 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-01-13   
443-378 2 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-01-13   
443-378 3 PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2006-02-10   
443-378 4 BLTMMDCHDS2  9212 VERIZON MARYLAND, INC. 238   2006-02-20   
443-378 5 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2004-09-23   
443-378 6 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-01-13   
443-378 7 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2004-09-23   
443-378 8 BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2004-09-23   
443-378 9 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-02-24   
443-386 A BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-386 0 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-386 1 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      

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

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