Local Calling Guide

Area code/prefix search

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Vienna, MD

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
410-376 A VINNMDVNRS0  9212 VERIZON MARYLAND, INC. 242      
410-376 0   9212 VERIZON MARYLAND, INC. 242      
410-376 1   2593 CORE COMMUNICATIONS, INC.- MD 242   2004-04-03   
410-376 2   9212 VERIZON MARYLAND, INC. 242      
410-376 3   9212 VERIZON MARYLAND, INC. 242      
410-376 4   876D ONVOY, LLC - MD 242   2019-03-04   
410-376 5   876D ONVOY, LLC - MD 242   2018-09-13   
410-376 6   876D ONVOY, LLC - MD 242   2019-03-04   
410-376 7   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 242   2006-11-07   
410-376 8   876D ONVOY, LLC - MD 242   2017-04-14   
410-376 9   145J TERRA NOVA TELECOM INC. 242   2024-02-14   
443-233 A   829J PAETEC ITEL, LLC 242   2025-04-01   
443-233 0   876D ONVOY, LLC - MD 242   2020-08-09   
443-233 1   876D ONVOY, LLC - MD 242   2020-08-09   
443-233 2   318J COMCAST IP PHONE, LLC 242   2007-08-08   
443-233 3   2593 CORE COMMUNICATIONS, INC.- MD 242   2018-06-17   
443-233 4   145J TERRA NOVA TELECOM INC. 242   2022-04-23   
443-233 5   876D ONVOY, LLC - MD 242   2020-10-17   
443-233 6   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 242   2012-05-26   
443-233 7   2593 CORE COMMUNICATIONS, INC.- MD 242   2018-06-17   
443-233 8   073H TELNYX LLC 242   2017-09-13   
443-233 9   829J PAETEC ITEL, LLC 242      
667-265 A ESTNMDESRMD  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 242      
667-265 0   624H ONVOY SPECTRUM, LLC 242   2021-11-15   
667-265 1   624H ONVOY SPECTRUM, LLC 242   2021-05-27   
667-265 2   876D ONVOY, LLC - MD 242   2020-10-17   
667-265 3   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 242   2019-06-18   
667-265 4   876D ONVOY, LLC - MD 242   2020-04-30   
667-265 5   876D ONVOY, LLC - MD 242   2020-04-30   
667-265 6   876D ONVOY, LLC - MD 242   2021-03-05   
667-265 7   876D ONVOY, LLC - MD 242   2023-06-17   
667-265 8   073H TELNYX LLC 242   2021-05-30   
667-265 9   624H ONVOY SPECTRUM, LLC 242   2021-11-15   
667-693 A SLBRMD90BMD  516J TON80 COMMUNICATIONS, LLC 242      
667-693 7   516J TON80 COMMUNICATIONS, LLC 242   2022-05-26   

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

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