Local Calling Guide

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Baltimore, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
443-529 8 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-06-26   
443-529 9 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-06-26   
443-531 A CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
443-531 0 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2009-06-23   
443-531 1 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2009-06-23   
443-531 2 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2009-06-23   
443-531 3 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2009-06-23   
443-531 4 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2009-06-23   
443-531 5 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2009-06-23   
443-531 6 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2009-06-23   
443-531 7 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2009-06-23   
443-531 8 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2009-06-23   
443-531 9 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2009-06-23   
443-540 A CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
443-552 A BLTMMDMDDS0  9212 VERIZON MARYLAND, INC. 238      
443-552 0 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-05-16   
443-552 1 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2016-01-05   
443-552 2 BLTMMDMDDS0  9212 VERIZON MARYLAND, INC. 238      
443-552 3 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-05-16   
443-552 4 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-05-16   
443-552 5 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-05-16   
443-552 6 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-04-20   
443-552 7 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-05-16   
443-552 8 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-04-20   
443-552 9 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-09-22   
443-560 A BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2024-02-09   
443-560 0 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-02-24   
443-560 1 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-09-01   
443-560 2 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-09-01   
443-560 3 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-09-01   
443-560 4 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-09-01   
443-560 5 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-09-01   
443-560 6 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-09-01   
443-560 7 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-09-01   
443-560 8 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-09-01   
443-560 9 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-09-01   
443-562 A CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
443-563 A BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-563 0 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2007-07-07   
443-563 1 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2007-09-25   
443-563 2 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2014-06-12   
443-563 3 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-04-04   
443-563 4 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2015-02-14   
443-563 5 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-04-04   
443-563 6 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2015-02-14   
443-563 7 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2015-02-14   
443-563 8 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2015-02-14   
443-563 9 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-04-04   
443-570 A BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-571 A 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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