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: 879

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-879 A Dundalk MD DNDLMDDNDS0  9212 VERIZON MARYLAND, INC. 238      
443-879 0 Dundalk MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   
443-879 1 Dundalk MD   829J PAETEC ITEL, LLC 238   2006-01-20   
443-879 2 Dundalk MD   876D ONVOY, LLC - MD 238   2014-09-05   
443-879 3 Dundalk MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2019-03-16   
443-879 4 Dundalk MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2018-11-11   
443-879 5 Dundalk MD   9212 VERIZON MARYLAND, INC. 238   2003-08-09   
443-879 6 Dundalk MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2018-07-28   
443-879 7 Dundalk MD   876D ONVOY, LLC - MD 238   2014-12-31   
443-879 8 Dundalk MD   876D ONVOY, LLC - MD 238   2014-12-31   
443-879 9 Dundalk MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2008-12-11   

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

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