Local Calling Guide

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Search area code/prefix (NPA/NXX)
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Cardiff, MD

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
410-452 A CRDFMDCDRS0  9212 VERIZON MARYLAND, INC. 238      
410-452 0   9212 VERIZON MARYLAND, INC. 238      
410-452 1   829J PAETEC ITEL, LLC 238   2003-02-25   
410-452 2   8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 238   2015-06-05   
410-452 3   876D ONVOY, LLC - MD 238   2016-04-04   
410-452 4   2596 QUANTUM TELECOMMUNICATIONS, INC. - MD 238   2003-12-25   
410-452 5   9212 VERIZON MARYLAND, INC. 238      
410-452 6   876D ONVOY, LLC - MD 238   2016-04-04   
410-452 7   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-01-02   
410-452 8   9212 VERIZON MARYLAND, INC. 238      
410-452 9   9212 VERIZON MARYLAND, INC. 238      
443-236 A BLTMMD91GT0  2593 CORE COMMUNICATIONS, INC.- MD 238      
443-347 A   829J PAETEC ITEL, LLC 238   2025-04-01   
443-347 0   876D ONVOY, LLC - MD 238   2016-03-31   
443-347 1   829J PAETEC ITEL, LLC 238      
443-347 2   071F BANDWIDTH.COM CLEC, LLC - MD 238   2019-03-07   
443-347 3   071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-07-04   
443-347 4   071F BANDWIDTH.COM CLEC, LLC - MD 238   2017-11-09   
443-347 5   876D ONVOY, LLC - MD 238   2016-03-14   
443-347 6   876D ONVOY, LLC - MD 238   2016-03-14   
443-347 7   508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-12   
443-347 8   073H TELNYX LLC 238   2017-04-26   
443-347 9   071F BANDWIDTH.COM CLEC, LLC - MD 238   2019-03-07   
443-424 A BLTMMDFMDS0  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-424 0   420C ARMSTRONG TELECOMMUNICATIONS, INC. - MD 238   2008-09-08   
443-424 1   829J PAETEC ITEL, LLC 238   2004-02-02   
443-424 2   071F BANDWIDTH.COM CLEC, LLC - MD 238   2008-12-11   
443-424 3   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-08-15   
443-424 4   071F BANDWIDTH.COM CLEC, LLC - MD 238   2019-03-07   
443-424 5   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-02-28   
443-424 6   876D ONVOY, LLC - MD 238   2012-10-07   
443-424 7   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-06-02   
443-424 8   071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-02-25   
443-424 9   7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-483 A BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-483 0   071F BANDWIDTH.COM CLEC, LLC - MD 238   2022-02-25   
443-483 1   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-483 2   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-483 3   071F BANDWIDTH.COM CLEC, LLC - MD 238   2019-03-07   
443-483 4   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2004-02-07   
443-483 5   624H ONVOY SPECTRUM, LLC 238   2022-02-13   
443-483 6   071F BANDWIDTH.COM CLEC, LLC - MD 238   2019-03-07   
443-483 7   071F BANDWIDTH.COM CLEC, LLC - MD 238   2019-03-07   
443-483 8   145J TERRA NOVA TELECOM INC. 238   2021-01-27   
443-483 9   624H ONVOY SPECTRUM, LLC 238   2022-02-13   
667-353 A BLTQMD01DS0  469J CORETEL MARYLAND, INC. - MD 238      
667-353 0   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2020-10-28   
667-353 1   5562 METROPCS, INC. 238   2021-05-28   
667-353 2   624H ONVOY SPECTRUM, LLC 238   2021-05-22   
667-353 4   876D ONVOY, LLC - MD 238   2021-03-04   
667-353 5   876D ONVOY, LLC - MD 238   2021-03-04   
667-353 7   876D ONVOY, LLC - MD 238   2021-12-19   
667-353 8   071F BANDWIDTH.COM CLEC, LLC - MD 238   2021-12-06   
667-353 9   469J CORETEL MARYLAND, INC. - MD 238   2019-11-11   
667-395 A BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238      
667-395 0   071F BANDWIDTH.COM CLEC, LLC - MD 238   2022-04-23   
667-395 1   071F BANDWIDTH.COM CLEC, LLC - MD 238   2022-04-24   
667-395 2   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2025-08-11   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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