Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 410 [Rate centres in NPA 410] [Dial plan for NPA 410]

NXX: 364

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
410-364 A Hillsboro MD HLBOMDTKRS0  9212 VERIZON MARYLAND, INC. 242      
410-364 0 Hillsboro MD   2593 CORE COMMUNICATIONS, INC.- MD 242   2004-04-03   
410-364 1 Hillsboro MD   624H ONVOY SPECTRUM, LLC 242   2024-06-24   
410-364 2 Hillsboro MD   624H ONVOY SPECTRUM, LLC 242   2024-06-24   
410-364 3 Hillsboro MD   228C IDT AMERICA, CORP. - MD 242   2006-05-21   
410-364 4 Hillsboro MD   876D ONVOY, LLC - MD 242   2017-04-13   
410-364 5 Hillsboro MD   9212 VERIZON MARYLAND, INC. 242      
410-364 6 Hillsboro MD   145J TERRA NOVA TELECOM INC. 242   2024-02-14   
410-364 7 Hillsboro MD   318J COMCAST IP PHONE, LLC 242   2008-08-30   
410-364 8 Hillsboro MD   073H TELNYX LLC 242   2017-09-13   
410-364 9 Hillsboro MD   9212 VERIZON MARYLAND, INC. 242      

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

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