Local Calling Guide

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NPA: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

NXX: 274

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-274 A Severn MD ODTNMDPORS2  9212 VERIZON MARYLAND, INC. 238      
443-274 0 Severn MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2008-02-27   
443-274 1 Severn MD BLTMMDCHW29  4716 PAETEC COMMUNICATIONS, INC. - MD 238   2005-10-17   
443-274 2 Severn MD BLTMMDCHXFX  318J COMCAST IP PHONE LLC 238   2007-09-20   
443-274 3 Severn MD BLTOMDKHDS0  7228 MCI WORLDCOM COMMUNICATIONS, INC. - MD 238   2008-10-01   
443-274 4 Severn MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2012-02-29   
443-274 5 Severn MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2013-04-22   
443-274 6 Severn MD BLTMMDCH21Z  5966 LIGHTWAVE COMMUNICATIONS, LLC - MD 238   2005-07-04   
443-274 7 Severn MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2013-04-22   
443-274 8 Severn MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2016-04-18   
443-274 9 Severn MD ODTNMDPORS2  9212 VERIZON MARYLAND, INC. 238      

Last updated: Tue, 04 May 2021 15:04:27 UTC

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