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: 577

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-577 A Glen Burnie MD   829J PAETEC ITEL, LLC 238   2025-04-01   
443-577 0 Glen Burnie MD   829J PAETEC ITEL, LLC 238      
443-577 1 Glen Burnie MD   829J PAETEC ITEL, LLC 238      
443-577 2 Glen Burnie MD   829J PAETEC ITEL, LLC 238      
443-577 3 Glen Burnie MD   829J PAETEC ITEL, LLC 238      
443-577 4 Glen Burnie MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2003-02-20   
443-577 5 Glen Burnie MD   829J PAETEC ITEL, LLC 238   2005-01-08   
443-577 6 Glen Burnie MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2022-11-24   
443-577 7 Glen Burnie MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-01   
443-577 8 Glen Burnie MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2016-07-14   
443-577 9 Glen Burnie MD   829J PAETEC ITEL, LLC 238      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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