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: MRBOMDMBDS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
301-298 4 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236   2013-02-25   
301-574 A Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-574 0 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-574 1 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-574 2 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-574 3 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-574 4 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-574 5 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-574 8 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-574 9 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-627 A Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-780 A Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-780 0 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-780 1 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-780 2 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-780 3 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-780 5 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-780 6 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-780 7 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-780 8 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-780 9 Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      
301-952 A Washington Zone 15 MD 9212 VERIZON MARYLAND, INC. 236      

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

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