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: 420

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-420 A Ellicott City MD   071F BANDWIDTH.COM CLEC, LLC - MD 238      
443-420 2 Ellicott City MD   5562 METROPCS, INC. 238   2018-10-05   
443-420 3 Ellicott City MD   318J COMCAST IP PHONE, LLC 238   2019-03-20   
443-420 5 Ellicott City MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2025-08-15   
443-420 6 Ellicott City MD   876D ONVOY, LLC - MD 238   2016-04-08   
443-420 7 Ellicott City MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-02-22   
443-420 8 Ellicott City MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-02-22   
443-420 9 Ellicott City MD   876D ONVOY, LLC - MD 238   2016-04-08   

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

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