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: LDVRMDLODS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
301-226 A Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-322 A Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-341 A Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-386 A Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-546 A Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-583 A Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-618 A Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-636 A Washington Zone 5 MD 9212 VERIZON MARYLAND, INC. 236      
301-772 A Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-773 A Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-883 A Washington Zone 5 MD 9212 VERIZON MARYLAND, INC. 236      
301-925 A Washington Zone 5 MD 9212 VERIZON MARYLAND, INC. 236      

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

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