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: LNHMMDLNDS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
301-306 A Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-429 A Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-459 A Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-552 A Washington Zone 13 MD 9212 VERIZON MARYLAND, INC. 236      
301-577 A Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-731 A Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-794 A Washington Zone 14 MD 9212 VERIZON MARYLAND, INC. 236      
301-794 0 Washington Zone 14 MD 9212 VERIZON MARYLAND, INC. 236      
301-794 1 Washington Zone 14 MD 9212 VERIZON MARYLAND, INC. 236      
301-794 3 Washington Zone 14 MD 9212 VERIZON MARYLAND, INC. 236      
301-794 4 Washington Zone 14 MD 9212 VERIZON MARYLAND, INC. 236      
301-794 5 Washington Zone 14 MD 9212 VERIZON MARYLAND, INC. 236      
301-794 6 Washington Zone 14 MD 9212 VERIZON MARYLAND, INC. 236      
301-794 7 Washington Zone 14 MD 9212 VERIZON MARYLAND, INC. 236      
301-794 8 Washington Zone 14 MD 9212 VERIZON MARYLAND, INC. 236      
301-794 9 Washington Zone 14 MD 9212 VERIZON MARYLAND, INC. 236      
301-918 A Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-918 0 Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-918 1 Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-918 2 Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-918 3 Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-918 4 Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-918 6 Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-918 7 Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-918 8 Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      
301-918 9 Washington Zone 4 MD 9212 VERIZON MARYLAND, INC. 236      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

Sponsored by: ISP Telecom

Like this site? We accept donations via PayPal.