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Washington Zone 10, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-354 0 WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-354 1 WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-354 2 WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-354 3 WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-354 4 WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-354 5 WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-354 6 WASIDCRG7MD  508J CENTURYLINK COMMUNICATIONS, LLC 236   2013-10-01   
301-354 7 WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-354 8 WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-354 9 WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-398 A RKVLMDRVDS1  9212 VERIZON MARYLAND, INC. 236      
301-398 0 RKVLMDRVDS1  9212 VERIZON MARYLAND, INC. 236   2003-11-09   
301-398 1 RKVLMDRVDS1  9212 VERIZON MARYLAND, INC. 236   2003-11-09   
301-398 2 RKVLMDRVDS1  9212 VERIZON MARYLAND, INC. 236   2003-11-09   
301-398 3 RKVLMDRVDS1  9212 VERIZON MARYLAND, INC. 236   2003-11-09   
301-398 4 RKVLMDRVDS1  9212 VERIZON MARYLAND, INC. 236   2003-11-09   
301-398 5 RKVLMDRVDS1  9212 VERIZON MARYLAND, INC. 236   2003-11-09   
301-398 6 RKVLMDRVDS1  9212 VERIZON MARYLAND, INC. 236   2003-11-09   
301-398 7 VINNVACBDS0  876D ONVOY, LLC - MD 236   2003-11-09   
301-398 8 VINNVACBDS0  876D ONVOY, LLC - MD 236   2003-11-09   
301-398 9 VINNVACBDS0  876D ONVOY, LLC - MD 236   2003-11-09   
301-417 A GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-417 0 GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-417 1 GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-417 2 GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-417 3   829J PAETEC ITEL, LLC 236   2015-09-17   
301-417 4 ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2015-04-14   
301-417 5 VINNVACBDS0  876D ONVOY, LLC - MD 236   2015-06-27   
301-417 6 GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-417 7 GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-417 8 ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2015-10-15   
301-417 9 GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-424 A RKVLMDRVDS1  9212 VERIZON MARYLAND, INC. 236      
301-428 A GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-444 A GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-444 0 GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-444 1 GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-444 2 GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-444 3 GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-444 4 RKVLMDRVDS1  9212 VERIZON MARYLAND, INC. 236   2007-02-06   
301-444 5   515J IP HORIZON LLC 236   2007-09-13   
301-444 6 SLSPMD91DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 236   2020-03-18   
301-444 7 GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236   2004-06-10   
301-444 8 GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-444 9 WASHDC127MD  073H TELNYX LLC 236   2020-01-28   
301-461 A WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236      
301-517 A RKVLMDRVDS1  9212 VERIZON MARYLAND, INC. 236      
301-517 0 RKVLMDRVDS1  9212 VERIZON MARYLAND, INC. 236      
301-517 1 RKVLMDRVDS1  9212 VERIZON MARYLAND, INC. 236      
301-517 2 RKVLMDRVDS1  9212 VERIZON MARYLAND, INC. 236      

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Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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