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: 491

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-491 A Parkton MD   876D ONVOY, LLC - MD 238      
443-491 2 Parkton MD   829J PAETEC ITEL, LLC 238   2005-10-07   
443-491 3 Parkton MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2005-03-10   
443-491 7 Parkton MD BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2020-09-04   
443-491 8 Parkton MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-11-18   
443-491 9 Parkton MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2012-10-07   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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