Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 301 [Rate centres in NPA 301] [Dial plan for NPA 301]

NXX: 444

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-444 A Washington Zone 10 MD GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-444 0 Washington Zone 10 MD GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-444 1 Washington Zone 10 MD GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-444 2 Washington Zone 10 MD GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-444 3 Washington Zone 10 MD GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-444 4 Washington Zone 10 MD RKVLMDRVDS1  9212 VERIZON MARYLAND, INC. 236   2007-02-06   
301-444 5 Washington Zone 10 MD   515J IP HORIZON LLC 236   2007-09-13   
301-444 6 Washington Zone 10 MD SLSPMD91DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 236   2020-03-18   
301-444 7 Washington Zone 10 MD GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236   2004-06-10   
301-444 8 Washington Zone 10 MD GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-444 9 Washington Zone 10 MD WASHDC127MD  073H TELNYX LLC 236   2020-01-28   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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