Local Calling Guide

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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 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-07-12   
443-300 1 Sykesville MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-04-29   
443-300 2 Sykesville MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-300 3 Sykesville MD BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2008-10-01   
443-300 4 Sykesville MD BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2021-06-26   
443-300 5 Sykesville MD BLTMMDCHXMX  506J TWILIO INTERNATIONAL, INC. 238   2020-12-26   
443-300 6 Sykesville MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-02-25   
443-300 7 Sykesville MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-09-03   
443-300 8 Sykesville MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-10-28   
443-300 9 Sykesville MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-07-12   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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