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: 607

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-607 A West River MD   829J PAETEC ITEL, LLC 238   2025-04-01   
443-607 0 West River MD   829J PAETEC ITEL, LLC 238      
443-607 1 West River MD   829J PAETEC ITEL, LLC 238   2003-03-02   
443-607 2 West River MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-06-05   
443-607 3 West River MD   829J PAETEC ITEL, LLC 238   2014-07-21   
443-607 4 West River MD   318J COMCAST IP PHONE, LLC 238   2013-08-09   
443-607 5 West River MD   568G PEERLESS NETWORK OF MARYLAND, LLC 238   2013-05-04   
443-607 6 West River MD   318J COMCAST IP PHONE, LLC 238   2007-10-11   
443-607 7 West River MD   829J PAETEC ITEL, LLC 238   2012-03-26   
443-607 8 West River MD   318J COMCAST IP PHONE, LLC 238   2006-12-14   
443-607 9 West River MD   515J IP HORIZON LLC 238   2016-01-04   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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