Local Calling Guide

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Washington Zone 10, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-978 1 BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2007-06-04   
301-978 2 GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-978 3   829J PAETEC ITEL, LLC 236   2013-01-25   
301-978 4 GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-978 5 GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-978 6 BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2007-10-12   
301-978 7 ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2014-09-18   
301-978 8 GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-978 9 GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-979 A   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236      
301-979 0 BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2008-08-18   
301-979 1 BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2008-04-21   
301-979 2 BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2008-04-21   
301-979 3 BTVLMD12CMA  5562 METROPCS, INC. 236   2013-08-06   
301-979 4 WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-979 5 BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2008-08-18   
301-979 6   829J PAETEC ITEL, LLC 236   2018-10-05   
301-979 7 MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2006-12-08   
301-979 8 BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2013-08-06   
301-979 9 MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2006-12-08   
301-983 A BTHSMDBDDS0  9212 VERIZON MARYLAND, INC. 236      

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Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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