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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
443-423 3 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-01-27   
443-423 4 Baltimore MD BLTMMDCHDS2  9212 VERIZON MARYLAND, INC. 238   2003-09-06   
443-423 5 Baltimore MD BLTMMDCHDS2  9212 VERIZON MARYLAND, INC. 238   2003-09-06   
443-423 6 Baltimore MD BLTMMDCHDS2  9212 VERIZON MARYLAND, INC. 238   2003-09-06   
443-423 7 Baltimore MD BLTMMDCHDS2  9212 VERIZON MARYLAND, INC. 238   2003-09-06   
443-423 8 Baltimore MD BLTMMDCHDS3  9212 VERIZON MARYLAND, INC. 238   2004-06-04   
443-423 9 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-01-27   
443-424 A Cardiff MD BLTMMDCHCMD  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-424 0 Cardiff MD BLTMMDCH47Z  420C ARMSTRONG TELECOMMUNICATIONS, INC. - MD 238   2008-09-08   
443-424 1 Cardiff MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2004-02-02   
443-424 2 Cardiff MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2008-12-11   
443-424 3 Cardiff MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-08-15   
443-424 4 Cardiff MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2019-03-07   
443-424 5 Cardiff MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-02-28   
443-424 6 Cardiff MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2012-10-07   
443-424 7 Cardiff MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-06-02   
443-424 8 Cardiff MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-02-25   
443-424 9 Cardiff MD BLTMMDCHCMD  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-425 A Parkville MD BLTMMDCHCMD  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-425 0 Parkville MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2012-05-21   
443-425 1 Parkville MD BLTMMDCHCMD  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-425 2 Parkville MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2012-05-21   
443-425 3 Parkville MD BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2008-10-01   
443-425 4 Parkville MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-11-17   
443-425 5 Parkville MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-11-17   
443-425 6 Parkville MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-11-17   
443-425 7 Parkville MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-11-17   
443-425 8 Parkville MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-11-17   
443-425 9 Parkville MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2015-06-30   
443-426 A Randallstown MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2025-04-01   
443-426 0 Randallstown MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-426 1 Randallstown MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-426 2 Randallstown MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-02-12   
443-426 3 Randallstown MD BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2021-05-23   
443-426 4 Randallstown MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2003-08-20   
443-426 5 Randallstown MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2003-03-04   
443-426 6 Randallstown MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238   2006-03-18   
443-426 7 Randallstown MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238   2004-06-25   
443-426 8 Randallstown MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-05-05   
443-426 9 Randallstown MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-427 A Princess Anne MD SLBRMD90DS0  2593 CORE COMMUNICATIONS, INC.- MD 242      
443-428 A Cockeysville MD BLTMMD91GT0  2593 CORE COMMUNICATIONS, INC.- MD 238      
443-429 A Woodlawn MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238   2025-04-01   
443-429 0 Woodlawn MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-07-02   
443-429 1 Woodlawn MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2012-10-08   
443-429 2 Woodlawn MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2014-04-17   
443-429 3 Woodlawn MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238   2001-11-01   
443-429 4 Woodlawn MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238   2001-11-01   
443-429 5 Woodlawn MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238   2001-11-01   
443-429 6 Woodlawn MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238   2001-11-01   

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

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