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: 585

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-585 A Darlington MD   829J PAETEC ITEL, LLC 238   2025-04-01   
443-585 0 Darlington MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-05-21   
443-585 1 Darlington MD   829J PAETEC ITEL, LLC 238      
443-585 2 Darlington MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-05-21   
443-585 3 Darlington MD   876D ONVOY, LLC - MD 238   2016-04-10   
443-585 4 Darlington MD   876D ONVOY, LLC - MD 238   2016-04-10   
443-585 5 Darlington MD   8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 238   2015-06-11   
443-585 6 Darlington MD   073H TELNYX LLC 238   2017-04-26   
443-585 7 Darlington MD   508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-12   
443-585 8 Darlington MD   876D ONVOY, LLC - MD 238   2014-09-19   
443-585 9 Darlington MD   876D ONVOY, LLC - MD 238   2014-09-19   

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

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