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: 300

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-300 A Sykesville MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-300 0 Sykesville MD   876D ONVOY, LLC - MD 238   2021-07-12   
443-300 1 Sykesville MD   876D ONVOY, LLC - MD 238   2021-04-29   
443-300 2 Sykesville MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-300 3 Sykesville MD   7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2008-10-01   
443-300 4 Sykesville MD   624H ONVOY SPECTRUM, LLC 238   2021-06-26   
443-300 5 Sykesville MD   506J TWILIO INTERNATIONAL INC 238   2020-12-26   
443-300 6 Sykesville MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-02-25   
443-300 7 Sykesville MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-09-03   
443-300 8 Sykesville MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-10-28   
443-300 9 Sykesville MD   876D ONVOY, LLC - MD 238   2021-07-12   

Last updated: Fri, 01 Jul 2022 02:53:40 UTC

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