Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

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

NXX: 679

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-679 A Severn MD BLTMMDFMDS0  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-679 0 Severn MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2020-04-22   
443-679 1 Severn MD   829J PAETEC ITEL, LLC 238   2002-04-22   
443-679 2 Severn MD   5562 METROPCS, INC. 238   2018-02-08   
443-679 3 Severn MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-05-14   
443-679 4 Severn MD   318J COMCAST IP PHONE, LLC 238   2016-12-15   
443-679 5 Severn MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2008-06-18   
443-679 6 Severn MD   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2012-05-31   
443-679 7 Severn MD   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2015-06-11   
443-679 8 Severn MD   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2014-06-04   
443-679 9 Severn MD   7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

Sponsored by: FiberConX Communications Ltd.

Like this site? We accept donations via PayPal.