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Columbia, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
667-257 6 BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2021-05-01   
667-257 7 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2019-11-26   
667-257 8   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-06-27   
667-257 9   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-06-27   
667-261 A CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
667-261 0 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2020-02-24   
667-261 1 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2020-02-24   
667-261 2 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2020-02-24   
667-261 3 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2020-04-08   
667-261 4 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2020-04-08   
667-261 5 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2020-04-08   
667-261 6 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-01-11   
667-261 7 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-01-11   
667-261 8 BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2020-06-21   
667-261 9 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2020-02-07   
667-300 A BLTMMD91GT0  2593 CORE COMMUNICATIONS, INC.- MD 238      
667-300 0   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-07-23   
667-300 1   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-07-23   
667-300 2 BLTMMDCHXQX  197D VONAGE AMERICA LLC 238   2018-12-06   
667-300 3   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-07-23   
667-300 4 BLTMMDCHXQX  197D VONAGE AMERICA LLC 238   2018-12-06   
667-300 5 BLTMMDCHXQX  197D VONAGE AMERICA LLC 238   2018-12-06   
667-300 6 BLTMMDCHXQX  197D VONAGE AMERICA LLC 238   2018-12-06   
667-300 7 BLTMMDCHXQX  197D VONAGE AMERICA LLC 238   2018-12-06   
667-300 8 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2018-08-04   
667-300 9 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2018-08-04   
667-359 A BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238      
667-359 0 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2021-12-26   
667-359 1 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2021-12-26   
667-359 2 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2021-12-26   
667-359 3 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2022-04-25   
667-359 4 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2022-12-18   
667-359 5 BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2022-08-27   
667-359 6 BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2022-01-15   
667-359 7 BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2022-01-15   
667-359 8 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2022-06-13   
667-359 9 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2022-06-13   
667-421 A BLTMMDCHX7X  073H TELNYX LLC 238      
667-421 0 BLTQMD019MD  490J DISH WIRELESS, LLC 238   2024-01-21   
667-421 1 BLTQMD019MD  490J DISH WIRELESS, LLC 238   2024-04-26   
667-421 2 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-02-25   
667-421 3 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-02-25   
667-421 4 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-12-23   
667-421 5 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-12-23   
667-421 6 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-12-23   
667-421 7 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2023-06-26   
667-421 8 BLTMMDCHX7X  073H TELNYX LLC 238   2023-04-24   
667-421 9 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2023-06-26   
667-447 A BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
667-447 0 BLTQMD019MD  490J DISH WIRELESS, LLC 238   2024-09-22   
667-447 1   876D ONVOY, LLC - MD 238   2025-09-06   
667-447 2 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-12-01   
667-447 3 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-12-23   
667-447 4   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2025-09-08   
667-447 5 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-12-23   
667-447 6 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-11-21   
667-447 7 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2023-10-07   
667-447 8 BLTQMD019MD  490J DISH WIRELESS, LLC 238   2025-01-22   
667-447 9 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2023-10-07   
667-502 A CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-02-10   
667-502 0   876D ONVOY, LLC - MD 238   2025-10-13   
667-502 2   490J DISH WIRELESS, LLC 238   2025-08-25   
667-502 3   490J DISH WIRELESS, LLC 238   2025-09-29   
667-502 4   490J DISH WIRELESS, LLC 238   2025-10-27   
667-502 5   876D ONVOY, LLC - MD 238   2025-03-02   
667-502 6 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-02-10   
667-502 7 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-02-10   
667-502 8 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-02-10   
667-502 9 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-02-10   
667-678 A BLTMMDCH42Z  876D ONVOY, LLC - MD 238      
667-678 0 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2021-10-16   
667-678 1 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2021-10-16   
667-678 2 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-10-15   
667-678 3 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2021-10-24   
667-678 4 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2021-10-24   
667-678 5 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2021-10-24   
667-678 6 BLTQMD013MD  939H COMMIO, LLC 238   2021-10-16   
667-678 7 BLTQMD013MD  939H COMMIO, LLC 238   2021-10-16   
667-678 8 BLTQMD013MD  939H COMMIO, LLC 238   2021-10-16   
667-678 9 BLTQMD013MD  939H COMMIO, LLC 238   2021-10-16   
667-786 A CLMAMDNIDS1  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
667-786 0 BLTMMDCH40Z  5562 METROPCS, INC. 238   2016-03-05   
667-786 1 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2016-01-05   
667-786 2 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2016-01-05   
667-786 3 CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2016-01-05   
667-786 4 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2016-02-05   
667-786 5 CLMAMDNIDS1  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238   2016-01-04   
667-786 6 CLMAMDNIDS1  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238   2016-01-04   
667-786 7 BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2016-03-14   
667-786 8 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2016-02-06   
667-786 9 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2016-02-06   

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Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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