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: 599

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-599 A Severn MD   5562 METROPCS, INC. 238      
443-599 0 Severn MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-04-08   
443-599 2 Severn MD BLTMMDCH40Z  5562 METROPCS, INC. 238   2013-06-14   
443-599 3 Severn MD BLTMMDCH40Z  5562 METROPCS, INC. 238   2013-06-14   
443-599 4 Severn MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-05-09   
443-599 5 Severn MD BLTMMDCH40Z  5562 METROPCS, INC. 238   2020-09-06   
443-599 6 Severn MD BLTMMDCH40Z  5562 METROPCS, INC. 238   2015-02-01   
443-599 7 Severn MD BLTMMDDN2MD  508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-25   
443-599 8 Severn MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-06-02   
443-599 9 Severn MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2008-12-11   

Last updated: Tue, 16 Jun 2026 00:09:45 UTC

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