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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
443-636 6 Catonsville MD BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2007-08-20   
443-636 7 Catonsville MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2008-07-17   
443-636 8 Catonsville MD BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2008-07-27   
443-636 9 Catonsville MD BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2008-07-27   
443-637 A Armiger-Gibson Island MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-637 0 Armiger-Gibson Island MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-637 1 Armiger-Gibson Island MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-01-10   
443-637 2 Armiger-Gibson Island MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-11-29   
443-637 3 Armiger-Gibson Island MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-637 4 Armiger-Gibson Island MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2003-02-20   
443-637 5 Armiger-Gibson Island MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-637 6 Armiger-Gibson Island MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2012-10-07   
443-637 7 Armiger-Gibson Island MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2012-10-11   
443-637 8 Armiger-Gibson Island MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2012-10-11   
443-637 9 Armiger-Gibson Island MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2012-10-11   
443-638 A Ellicott City MD BLTMMDDN4MD  2554 GLOBAL NAPS SOUTH, INC. - MD 238      
443-639 A Hampstead MD PIVLMDPKXFX  829J PAETEC ITEL, LLC 238   2025-04-01   
443-639 0 Hampstead MD BLTMMDCHX7X  073H TELNYX LLC 238   2017-04-26   
443-639 1 Hampstead MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-05-23   
443-639 2 Hampstead MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2017-07-07   
443-639 3 Hampstead MD PIVLMDPKXFX  829J PAETEC ITEL, LLC 238      
443-639 4 Hampstead MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-06-04   
443-639 5 Hampstead MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2015-04-02   
443-639 6 Hampstead MD BLTMMDCH25Z  8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 238   2015-06-13   
443-639 7 Hampstead MD BLTMMDDN2MD  508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-12   
443-639 8 Hampstead MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2014-10-21   
443-639 9 Hampstead MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2014-10-21   
443-640 A Bel Air MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2025-04-01   
443-640 0 Bel Air MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-640 1 Bel Air MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-640 2 Bel Air MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-640 3 Bel Air MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-640 4 Bel Air MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2008-04-30   
443-640 5 Bel Air MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2009-02-02   
443-640 6 Bel Air MD BLTMMDCH47Z  420C ARMSTRONG TELECOMMUNICATIONS, INC. - MD 238   2008-09-08   
443-640 7 Bel Air MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2012-03-16   
443-640 8 Bel Air MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2008-04-21   
443-640 9 Bel Air MD BLTMMDCHX7X  073H TELNYX LLC 238   2021-03-04   
443-641 A Pikesville MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-641 0 Pikesville MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-641 1 Pikesville MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-641 2 Pikesville MD OWMLMDOMDS0  9212 VERIZON MARYLAND, INC. 238   2004-10-10   
443-641 3 Pikesville MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2011-08-05   
443-641 4 Pikesville MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2011-08-05   
443-641 5 Pikesville MD OWMLMDOMDS0  9212 VERIZON MARYLAND, INC. 238   2004-10-10   
443-641 6 Pikesville MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2011-11-28   
443-641 7 Pikesville MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2011-11-28   
443-641 8 Pikesville MD BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-641 9 Pikesville MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-642 A Baltimore MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      

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

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