Local Calling Guide

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

NXX: 203

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-203 A West River MD MAYOMDMYRS1  9212 VERIZON MARYLAND, INC. 238      
443-203 0 West River MD MAYOMDMYRS1  9212 VERIZON MARYLAND, INC. 238      
443-203 1 West River MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-04-03   
443-203 2 West River MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2008-06-20   
443-203 3 West River MD BLTQMD018MD  145J TERRA NOVA TELECOM INC. 238   2024-07-16   
443-203 4 West River MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2003-08-20   
443-203 5 West River MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-03-31   
443-203 6 West River MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2005-03-10   
443-203 7 West River MD BLTMMDDN2MD  508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-25   
443-203 8 West River MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-06-26   
443-203 9 West River MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2008-12-11   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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