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NPA: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

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NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-577 4 Glen Burnie MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2003-02-20   
443-577 5 Glen Burnie MD PIVLMDPKXFX  829J PAETEC ITEL, LLC 238   2005-01-08   
443-577 6 Glen Burnie MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2022-11-24   
443-577 7 Glen Burnie MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-01   
443-577 8 Glen Burnie MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2016-07-14   
443-577 9 Glen Burnie MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-578 A Cockeysville MD BLTMMDSNDS5  4773 XO MARYLAND, LLC 238      
443-578 0 Cockeysville MD BLTMMDSNDS5  4773 XO MARYLAND, LLC 238      
443-578 1 Cockeysville MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2014-10-21   
443-578 2 Cockeysville MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2015-10-26   
443-578 3 Cockeysville MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2012-02-27   
443-578 4 Cockeysville MD BLTMMDSNDS5  4773 XO MARYLAND, LLC 238      
443-578 5 Cockeysville MD BLTMMDSNDS5  4773 XO MARYLAND, LLC 238      
443-578 6 Cockeysville MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2013-08-15   
443-578 7 Cockeysville MD BLTMMDDN2MD  508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-25   
443-578 8 Cockeysville MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2008-09-26   
443-578 9 Cockeysville MD   515J IP HORIZON LLC 238   2015-03-23   
443-579 A Essex MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2025-04-01   
443-579 0 Essex MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-579 1 Essex MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-579 2 Essex MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-579 3 Essex MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-579 4 Essex MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-06-26   
443-579 5 Essex MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2008-12-11   
443-579 6 Essex MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2008-07-17   
443-579 7 Essex MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-10-28   
443-579 8 Essex MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-02-26   
443-579 9 Essex MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-580 A Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2024-02-09   
443-580 0 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-10-27   
443-580 1 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-10-27   
443-580 2 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-10-27   
443-580 3 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-10-27   
443-580 4 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-10-27   
443-580 5 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-10-27   
443-580 6 Baltimore MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-04-13   
443-580 7 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-10-27   
443-580 8 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-10-27   
443-580 9 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-10-27   
443-581 A Chase MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238      
443-581 0 Chase MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-03-04   
443-581 1 Chase MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-03-04   
443-581 2 Chase MD   876D ONVOY, LLC - MD 238   2026-09-05   
443-581 3 Chase MD   145J TERRA NOVA TELECOM INC. 238   2024-09-12   
443-581 4 Chase MD BLTQMD018MD  145J TERRA NOVA TELECOM INC. 238   2026-07-04   
443-581 5 Chase MD BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2021-02-24   
443-581 6 Chase MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-07-30   
443-581 7 Chase MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-07-30   
443-581 8 Chase MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2019-07-06   
443-581 9 Chase MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   

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Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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