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: RKVLMDMRDS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
240-221 A Washington Zone 11 MD 9212 VERIZON MARYLAND, INC. 236      
301-230 A Washington Zone 11 MD 9212 VERIZON MARYLAND, INC. 236      
301-231 A Washington Zone 11 MD 9212 VERIZON MARYLAND, INC. 236      
301-255 A Washington Zone 11 MD 9212 VERIZON MARYLAND, INC. 236      
301-382 A Washington Zone 11 MD 9212 VERIZON MARYLAND, INC. 236      
301-413 A Washington Zone 11 MD 9212 VERIZON MARYLAND, INC. 236      
301-468 A Washington Zone 11 MD 9212 VERIZON MARYLAND, INC. 236      
301-522 A Washington Zone 11 MD 9212 VERIZON MARYLAND, INC. 236      
301-770 A Washington Zone 11 MD 9212 VERIZON MARYLAND, INC. 236      
301-816 A Washington Zone 11 MD 9212 VERIZON MARYLAND, INC. 236      
301-881 A Washington Zone 11 MD 9212 VERIZON MARYLAND, INC. 236      
301-984 A Washington Zone 11 MD 9212 VERIZON MARYLAND, INC. 236      
301-998 A Washington Zone 11 MD 9212 VERIZON MARYLAND, INC. 236      

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

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