Local Calling Guide

Area code/prefix search

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

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
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 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   

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

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