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.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

Switch: PSTNMDPSRS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
410-673 A Preston MD 9212 VERIZON MARYLAND, INC. 242      
410-673 1 Preston MD 9212 VERIZON MARYLAND, INC. 242      
410-673 2 Preston MD 9212 VERIZON MARYLAND, INC. 242      
410-673 7 Preston MD 9212 VERIZON MARYLAND, INC. 242      
410-673 9 Preston MD 9212 VERIZON MARYLAND, INC. 242      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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