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: 672

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-672 A Parkton MD BLTMMDFMDS0  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-672 0 Parkton MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2004-04-02   
443-672 1 Parkton MD   829J PAETEC ITEL, LLC 238   2004-01-31   
443-672 2 Parkton MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-02-25   
443-672 3 Parkton MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-03-29   
443-672 4 Parkton MD   876D ONVOY, LLC - MD 238   2019-02-19   
443-672 5 Parkton MD   876D ONVOY, LLC - MD 238   2019-02-19   
443-672 6 Parkton MD   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-672 7 Parkton MD   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-672 8 Parkton MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2012-10-12   
443-672 9 Parkton MD   7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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