Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 667 [Rate centres in NPA 667] [Dial plan for NPA 667]

NXX: 403

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
667-403 A Towson MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238      
667-403 0 Towson MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2021-11-01   
667-403 1 Towson MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2021-11-01   
667-403 2 Towson MD   876D ONVOY, LLC - MD 238   2021-10-31   
667-403 3 Towson MD   624H ONVOY SPECTRUM, LLC 238   2021-11-18   
667-403 4 Towson MD   624H ONVOY SPECTRUM, LLC 238   2021-11-18   
667-403 5 Towson MD   624H ONVOY SPECTRUM, LLC 238   2021-11-18   
667-403 6 Towson MD   939H COMMIO, LLC 238   2021-11-01   
667-403 7 Towson MD   939H COMMIO, LLC 238   2021-11-01   
667-403 8 Towson MD   939H COMMIO, LLC 238   2021-11-01   
667-403 9 Towson MD   939H COMMIO, LLC 238   2021-11-01   

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

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