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: 507

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-507 A Hampstead MD BLTMMDFMDS0  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-507 0 Hampstead MD HMPSMDHERS1  9212 VERIZON MARYLAND, INC. 238   2003-10-17   
443-507 1 Hampstead MD CLMAMDJTAMD  2589 US LEC OF MARYLAND, INC. 238   2003-07-20   
443-507 2 Hampstead MD   145J TERRA NOVA TELECOM INC. 238   2022-07-06   
443-507 3 Hampstead MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2004-03-29   
443-507 4 Hampstead MD BLTMMD91DS2  2596 QUANTUM TELECOMMUNICATIONS, INC. - MD 238   2016-01-31   
443-507 5 Hampstead MD HMPSMDHERS1  9212 VERIZON MARYLAND, INC. 238   2005-05-27   
443-507 6 Hampstead MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2009-06-13   
443-507 7 Hampstead MD   145J TERRA NOVA TELECOM INC. 238   2024-02-15   
443-507 8 Hampstead MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-07-02   
443-507 9 Hampstead MD BLTMMDFMDS0  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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