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: 584

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-584 A Crofton MD   829J PAETEC ITEL, LLC 238   2025-04-01   
443-584 0 Crofton MD   624H ONVOY SPECTRUM, LLC 238   2021-05-22   
443-584 1 Crofton MD   829J PAETEC ITEL, LLC 238      
443-584 2 Crofton MD   145J TERRA NOVA TELECOM INC. 238   2024-02-15   
443-584 3 Crofton MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2014-06-06   
443-584 4 Crofton MD   318J COMCAST IP PHONE, LLC 238   2014-07-20   
443-584 5 Crofton MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-05-21   
443-584 6 Crofton MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-05-21   
443-584 7 Crofton MD   508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-25   
443-584 8 Crofton MD   515J IP HORIZON LLC 238   2016-10-14   
443-584 9 Crofton MD   515J IP HORIZON LLC 238   2015-03-21   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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