Local Calling Guide

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Towson, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
667-403 5 BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2021-11-18   
667-403 6 BLTQMD013MD  939H COMMIO, LLC 238   2021-11-01   
667-403 7 BLTQMD013MD  939H COMMIO, LLC 238   2021-11-01   
667-403 8 BLTQMD013MD  939H COMMIO, LLC 238   2021-11-01   
667-403 9 BLTQMD013MD  939H COMMIO, LLC 238   2021-11-01   
667-436 A BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
667-436 0 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-12-14   
667-436 1 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-12-14   
667-436 2 BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2024-11-20   
667-436 3 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-04-19   
667-436 4 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-04-19   
667-436 5 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-04-19   
667-436 6 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2025-11-28   
667-436 7 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2023-10-07   
667-436 8 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2023-10-07   
667-436 9 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2023-07-03   
667-548 A BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2026-07-23   
667-548 0 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2026-07-23   
667-548 1   876D ONVOY, LLC - MD 238   2026-09-17   
667-548 2   876D ONVOY, LLC - MD 238   2026-09-17   
667-548 6   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2026-10-01   
667-548 7   820C INTRADO COMMUNICATIONS, LLC 238   2026-10-10   
667-548 8   071F BANDWIDTH.COM CLEC, LLC - MD 238   2026-10-16   
667-548 9   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2026-10-01   

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

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