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: 584

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
410-584 A Cockeysville MD CYVLMDDADS0  9212 VERIZON MARYLAND, INC. 238      
410-584 0 Cockeysville MD   9212 VERIZON MARYLAND, INC. 238      
410-584 1 Cockeysville MD   9212 VERIZON MARYLAND, INC. 238      
410-584 2 Cockeysville MD   9212 VERIZON MARYLAND, INC. 238      
410-584 3 Cockeysville MD   876D ONVOY, LLC - MD 238   2024-03-08   
410-584 4 Cockeysville MD   9212 VERIZON MARYLAND, INC. 238      
410-584 5 Cockeysville MD   876D ONVOY, LLC - MD 238   2024-03-08   
410-584 6 Cockeysville MD   9212 VERIZON MARYLAND, INC. 238      
410-584 7 Cockeysville MD   9212 VERIZON MARYLAND, INC. 238      
410-584 8 Cockeysville MD   9212 VERIZON MARYLAND, INC. 238      
410-584 9 Cockeysville MD   9212 VERIZON MARYLAND, INC. 238      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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