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: 347

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-347 A Cardiff MD   829J PAETEC ITEL, LLC 238   2025-04-01   
443-347 0 Cardiff MD   876D ONVOY, LLC - MD 238   2016-03-31   
443-347 1 Cardiff MD   829J PAETEC ITEL, LLC 238      
443-347 2 Cardiff MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2019-03-07   
443-347 3 Cardiff MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-07-04   
443-347 4 Cardiff MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2017-11-09   
443-347 5 Cardiff MD   876D ONVOY, LLC - MD 238   2016-03-14   
443-347 6 Cardiff MD   876D ONVOY, LLC - MD 238   2016-03-14   
443-347 7 Cardiff MD   508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-12   
443-347 8 Cardiff MD   073H TELNYX LLC 238   2017-04-26   
443-347 9 Cardiff MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2019-03-07   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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