Local Calling Guide

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Washington Zone 15 (Baltimore LATA), MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-494 0 PRFRMDPFRS1  9212 VERIZON MARYLAND, INC. 238      
301-494 1 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2012-06-25   
301-494 2 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2015-03-27   
301-494 3 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-03-06   
301-494 4 BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2011-03-11   
301-494 5 BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2011-06-17   
301-494 6 BLTMMDDN2MD  508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-25   
301-494 7 BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2011-06-17   
301-494 8 BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-05   
301-494 9 BLTQMD01DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-05   
301-812 A NRBHMDNEDS0  9212 VERIZON MARYLAND, INC. 238      
301-812 0 NRBHMDNEDS0  9212 VERIZON MARYLAND, INC. 238      
301-812 1 NRBHMDNEDS0  9212 VERIZON MARYLAND, INC. 238      
301-812 2 NRBHMDNEDS0  9212 VERIZON MARYLAND, INC. 238      
301-812 3 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2015-09-05   
301-812 4 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2012-10-08   
301-812 5 PIVLMDPKXFX  829J PAETEC ITEL, LLC 238   2013-08-28   
301-812 6 BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2013-11-26   
301-812 7 BLTMMDSNDS6  281E YMAX COMMUNICATIONS CORP. - MD 238   2010-10-04   
301-812 8 BLTMMDCH25Z  8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 238   2015-06-22   
301-812 9 PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2004-01-31   
301-855 A NRBHMDNEDS0  9212 VERIZON MARYLAND, INC. 238      

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Last updated: Tue, 01 Sep 2026 00:40:05 UTC

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