Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

NXX: 424

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-424 A Cardiff MD BLTMMDFMDS0  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-424 0 Cardiff MD BLTMMDCH47Z  420C ARMSTRONG TELECOMMUNICATIONS, INC. - MD 238   2008-09-08   
443-424 1 Cardiff MD CLMAMDJTAMD  2589 US LEC OF MARYLAND, INC. 238   2004-02-02   
443-424 2 Cardiff MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2008-12-11   
443-424 3 Cardiff MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-08-15   
443-424 4 Cardiff MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2019-03-07   
443-424 5 Cardiff MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-02-28   
443-424 6 Cardiff MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2012-10-07   
443-424 7 Cardiff MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-06-02   
443-424 8 Cardiff MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-02-25   
443-424 9 Cardiff MD BLTMMDFMDS0  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      

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

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