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: 399

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
410-399 A Bel Air MD CRDFMDCDRS0  9212 VERIZON MARYLAND, INC. 238      
410-399 0 Bel Air MD   9212 VERIZON MARYLAND, INC. 238      
410-399 1 Bel Air MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-10-11   
410-399 2 Bel Air MD   9212 VERIZON MARYLAND, INC. 238      
410-399 3 Bel Air MD   829J PAETEC ITEL, LLC 238   2003-03-11   
410-399 4 Bel Air MD   9212 VERIZON MARYLAND, INC. 238      
410-399 5 Bel Air MD   8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 238   2015-06-05   
410-399 6 Bel Air MD   9212 VERIZON MARYLAND, INC. 238      
410-399 7 Bel Air MD   9212 VERIZON MARYLAND, INC. 238      
410-399 8 Bel Air MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-10-11   
410-399 9 Bel Air MD   9212 VERIZON MARYLAND, INC. 238      

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

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