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Westminster, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
443-952 9   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-974 A BLTMMDFMDS0  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-974 0   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2007-03-05   
443-974 1   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2007-06-01   
443-974 2   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2006-07-19   
443-974 3   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2006-07-19   
443-974 4   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2008-10-03   
443-974 5   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2006-09-23   
443-974 6   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2006-11-02   
443-974 7   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2007-01-02   
443-974 8   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2007-02-02   
443-974 9   7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
667-272 A CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
667-272 0   876D ONVOY, LLC - MD 238   2021-09-23   
667-272 1   624H ONVOY SPECTRUM, LLC 238   2021-05-23   
667-272 2   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2025-05-22   
667-272 3   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2022-06-15   
667-272 4   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2019-11-02   
667-272 5   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2019-11-02   
667-272 6   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2019-11-02   
667-272 7   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2019-11-02   
667-272 8   516J TON80 COMMUNICATIONS, LLC 238   2021-07-14   
667-272 9   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2019-11-02   
667-314 A BLTQMD012MD  964H BARR TELL USA, INC. 238      
667-314 0   071F BANDWIDTH.COM CLEC, LLC - MD 238   2019-07-12   
667-314 1   964H BARR TELL USA, INC. 238   2016-12-17   
667-314 2   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2016-09-27   
667-314 3   318J COMCAST IP PHONE, LLC 238   2017-10-30   
667-314 4   073H TELNYX LLC 238   2017-03-14   
667-314 5   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2017-10-02   
667-314 6   876D ONVOY, LLC - MD 238   2021-07-12   
667-314 7   145J TERRA NOVA TELECOM INC. 238   2024-02-15   
667-314 8   876D ONVOY, LLC - MD 238   2024-04-14   
667-314 9   876D ONVOY, LLC - MD 238   2024-04-14   
667-367 A BLTMMDSN3MD  8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 238      
667-367 0   515J IP HORIZON LLC 238   2016-05-31   
667-367 1   071F BANDWIDTH.COM CLEC, LLC - MD 238   2016-09-08   
667-367 2   318J COMCAST IP PHONE, LLC 238   2016-06-15   
667-367 3   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2015-11-13   
667-367 4   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2016-07-25   
667-367 5   876D ONVOY, LLC - MD 238   2016-01-22   
667-367 6   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2016-10-31   
667-367 7   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2016-05-06   
667-367 8   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2018-04-23   
667-367 9   8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 238   2015-07-12   
667-484 A BLTQMD019MD  490J DISH WIRELESS, LLC 238   2024-07-12   
667-484 0   490J DISH WIRELESS, LLC 238   2024-07-12   
667-484 1   490J DISH WIRELESS, LLC 238   2024-07-12   
667-484 2   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2026-02-05   
667-484 6   876D ONVOY, LLC - MD 238   2026-01-11   

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Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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