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: 837

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-837 A Annapolis MD   829J PAETEC ITEL, LLC 238   2025-04-01   
443-837 0 Annapolis MD   829J PAETEC ITEL, LLC 238      
443-837 1 Annapolis MD   829J PAETEC ITEL, LLC 238      
443-837 2 Annapolis MD   829J PAETEC ITEL, LLC 238      
443-837 3 Annapolis MD   829J PAETEC ITEL, LLC 238      
443-837 4 Annapolis MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2023-01-30   
443-837 5 Annapolis MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2008-12-11   
443-837 6 Annapolis MD   318J COMCAST IP PHONE, LLC 238   2008-02-17   
443-837 7 Annapolis MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-02-26   
443-837 8 Annapolis MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2007-12-20   
443-837 9 Annapolis MD   829J PAETEC ITEL, LLC 238      

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

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