Local Calling Guide

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

NXX: 273

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-273 A Reisterstown MD CLMAMDNIDS1  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-273 0 Reisterstown MD CLMAMDNIDS1  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-273 1 Reisterstown MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-07-02   
443-273 2 Reisterstown MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-03-22   
443-273 3 Reisterstown MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2014-09-21   
443-273 4 Reisterstown MD BLTMMDCH40Z  5562 METROPCS, INC. 238   2014-09-28   
443-273 5 Reisterstown MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2012-10-08   
443-273 6 Reisterstown MD BLTMMDCH40Z  5562 METROPCS, INC. 238   2014-11-03   
443-273 7 Reisterstown MD BLTMMDDN2MD  508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-25   
443-273 8 Reisterstown MD   515J IP HORIZON LLC 238   2016-01-04   
443-273 9 Reisterstown MD CLMAMDNIDS1  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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