Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
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Switch: CLMAMDSRRS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
410-312 A Columbia MD 9212 VERIZON MARYLAND, INC. 238      
410-872 A Columbia MD 9212 VERIZON MARYLAND, INC. 238      
410-953 A Columbia MD 9212 VERIZON MARYLAND, INC. 238      
410-953 0 Columbia MD 9212 VERIZON MARYLAND, INC. 238      
410-953 1 Columbia MD 9212 VERIZON MARYLAND, INC. 238      
410-953 2 Columbia MD 9212 VERIZON MARYLAND, INC. 238      
410-953 3 Columbia MD 9212 VERIZON MARYLAND, INC. 238      
410-953 4 Columbia MD 9212 VERIZON MARYLAND, INC. 238      
410-953 5 Columbia MD 9212 VERIZON MARYLAND, INC. 238      
410-953 6 Columbia MD 9212 VERIZON MARYLAND, INC. 238      
410-953 7 Columbia MD 9212 VERIZON MARYLAND, INC. 238      
410-953 8 Columbia MD 9212 VERIZON MARYLAND, INC. 238      
443-285 A Columbia MD 9212 VERIZON MARYLAND, INC. 238      
443-285 0 Columbia MD 9212 VERIZON MARYLAND, INC. 238      
443-285 4 Columbia MD 9212 VERIZON MARYLAND, INC. 238      
443-285 5 Columbia MD 9212 VERIZON MARYLAND, INC. 238      
443-285 7 Columbia MD 9212 VERIZON MARYLAND, INC. 238      
443-285 8 Columbia MD 9212 VERIZON MARYLAND, INC. 238      
443-542 4 Columbia MD 9212 VERIZON MARYLAND, INC. 238   2004-12-20   
443-542 6 Columbia MD 9212 VERIZON MARYLAND, INC. 238   2004-12-20   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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