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: 737

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-737 A Waterloo MD   829J PAETEC ITEL, LLC 238   2025-04-01   
443-737 0 Waterloo MD   829J PAETEC ITEL, LLC 238      
443-737 1 Waterloo MD   829J PAETEC ITEL, LLC 238      
443-737 2 Waterloo MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-07-16   
443-737 3 Waterloo MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-02   
443-737 4 Waterloo MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2004-02-07   
443-737 5 Waterloo MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-05-02   
443-737 6 Waterloo MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-03-21   
443-737 7 Waterloo MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-03-21   
443-737 8 Waterloo MD   515J IP HORIZON LLC 238   2015-03-21   
443-737 9 Waterloo MD   829J PAETEC ITEL, LLC 238      

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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