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Gaithersburg, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-355 5   9212 VERIZON MARYLAND, INC. 236   2007-09-04   
301-355 6   9212 VERIZON MARYLAND, INC. 236   2007-09-04   
301-355 7   9212 VERIZON MARYLAND, INC. 236   2007-09-04   
301-355 8   318J COMCAST IP PHONE, LLC 236   2009-08-28   
301-355 9   281E YMAX COMMUNICATIONS CORP. - MD 236   2011-02-02   
301-366 A BTVLMD12CMA  5562 METROPCS, INC. 236      
301-366 0   318J COMCAST IP PHONE, LLC 236   2013-09-12   
301-366 1   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2010-06-17   
301-366 2   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2010-06-17   
301-366 3   5562 METROPCS, INC. 236   2003-10-11   
301-366 4   5562 METROPCS, INC. 236   2003-10-11   
301-366 5   5562 METROPCS, INC. 236   2004-10-03   
301-366 6   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2010-06-17   
301-366 7   5562 METROPCS, INC. 236   2003-12-30   
301-366 8   5562 METROPCS, INC. 236   2003-12-30   
301-366 9   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2010-09-27   
301-370 A BTVLMD12CMA  5562 METROPCS, INC. 236      
301-370 0   5562 METROPCS, INC. 236      
301-370 1   5562 METROPCS, INC. 236      
301-370 2   5562 METROPCS, INC. 236      
301-370 3   5562 METROPCS, INC. 236      
301-370 4   5562 METROPCS, INC. 236      
301-370 5   5562 METROPCS, INC. 236      
301-370 6   5562 METROPCS, INC. 236      
301-370 7   5562 METROPCS, INC. 236      
301-370 8   5562 METROPCS, INC. 236      
301-370 9   5562 METROPCS, INC. 236      
301-407 A PLVLMDPVRS2  9212 VERIZON MARYLAND, INC. 236      
301-407 0   9212 VERIZON MARYLAND, INC. 236      
301-407 1   318J COMCAST IP PHONE, LLC 236   2011-06-10   
301-407 2   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2014-10-23   
301-407 3   5562 METROPCS, INC. 236   2005-07-14   
301-407 4   9212 VERIZON MARYLAND, INC. 236   2003-05-10   
301-407 5   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2006-05-05   
301-407 6   829J PAETEC ITEL, LLC 236   2011-10-13   
301-407 7   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2005-12-29   
301-407 8   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2006-05-05   
301-407 9   9212 VERIZON MARYLAND, INC. 236      
301-515 A GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-519 A GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-525 A LARLMDLR3MD  2596 QUANTUM TELECOMMUNICATIONS, INC. - MD 236      
301-525 0   2596 QUANTUM TELECOMMUNICATIONS, INC. - MD 236   2003-12-07   
301-525 1   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2008-06-05   
301-525 2   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2008-08-14   
301-525 3   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2008-10-03   
301-525 4   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2008-02-15   
301-525 5   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2008-02-15   
301-525 6   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2008-07-03   
301-525 7   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2008-11-03   
301-525 8   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2008-11-17   
301-525 9   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2008-12-19   
301-527 A GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-528 A GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-540 A GMTWMDGNDS0  9212 VERIZON MARYLAND, INC. 236      
301-556 A WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-556 0   7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-556 1   7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-556 2   7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-556 3   5562 METROPCS, INC. 236   2004-11-18   
301-556 4   7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-556 5   4492 VDL, INC. DBA GLOBAL TELECOM BROKERS - MD 236   2004-05-06   
301-556 6   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2004-02-28   
301-556 7   5562 METROPCS, INC. 236   2004-02-28   
301-556 8   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2005-11-13   
301-556 9   7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-569 A WASKDCFNAMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236      
301-569 0   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2013-09-17   
301-569 1   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2014-05-01   
301-569 2   071F BANDWIDTH.COM CLEC, LLC - MD 236   2011-05-07   
301-569 3   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 236   2014-06-01   
301-569 4   318J COMCAST IP PHONE, LLC 236   2013-12-10   
301-569 5   508J CENTURYLINK COMMUNICATIONS, LLC 236   2013-10-01   
301-569 6   318J COMCAST IP PHONE, LLC 236   2011-09-08   
301-569 7   318J COMCAST IP PHONE, LLC 236   2012-01-14   
301-569 8   281E YMAX COMMUNICATIONS CORP. - MD 236   2011-09-02   
301-569 9   876D ONVOY, LLC - MD 236   2012-04-05   
301-591 A   829J PAETEC ITEL, LLC 236   2025-04-02   
301-591 0   829J PAETEC ITEL, LLC 236      
301-591 1   829J PAETEC ITEL, LLC 236      
301-591 2   829J PAETEC ITEL, LLC 236      
301-591 3   829J PAETEC ITEL, LLC 236      
301-591 4   829J PAETEC ITEL, LLC 236      
301-591 5   829J PAETEC ITEL, LLC 236      
301-591 6   568G PEERLESS NETWORK OF MARYLAND, LLC 236   2020-04-19   
301-591 7   876D ONVOY, LLC - MD 236   2021-02-18   
301-591 8   829J PAETEC ITEL, LLC 236      
301-591 9   829J PAETEC ITEL, LLC 236      
301-740 A GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-740 0   5562 METROPCS, INC. 236   2004-11-29   
301-740 1   9212 VERIZON MARYLAND, INC. 236   2004-07-02   
301-740 2   9212 VERIZON MARYLAND, INC. 236   2004-07-02   
301-740 3   9212 VERIZON MARYLAND, INC. 236   2004-07-02   
301-740 4   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2005-04-07   
301-740 5   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2006-02-05   
301-740 6   281E YMAX COMMUNICATIONS CORP. - MD 236   2011-09-02   
301-740 7   9212 VERIZON MARYLAND, INC. 236   2006-03-30   
301-740 8   9212 VERIZON MARYLAND, INC. 236   2006-03-30   
301-740 9   9212 VERIZON MARYLAND, INC. 236   2006-03-30   
301-820 A WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-820 0   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2012-02-23   

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Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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