Local Calling Guide

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NPA: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

NXX: 583

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-583 A Columbia MD BLTMMDCH14Z  2697 CTC COMMUNICATIONS CORP. - MD 238      
443-583 0 Columbia MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-03-03   
443-583 1 Columbia MD BLTMMDCH14Z  2697 CTC COMMUNICATIONS CORP. - MD 238      
443-583 2 Columbia MD BLTMMD91DS2  2596 QUANTUM TELECOMMUNICATIONS, INC. - MD 238   2016-01-31   
443-583 3 Columbia MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2014-03-31   
443-583 4 Columbia MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2014-03-31   
443-583 5 Columbia MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2014-09-01   
443-583 6 Columbia MD BLTMMDCHFMD  5562 METROPCS, INC. 238   2015-05-29   
443-583 7 Columbia MD BLTMMDCHXFX  318J COMCAST IP PHONE LLC 238   2014-09-16   
443-583 8 Columbia MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-05-14   
443-583 9 Columbia MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC DBA T-MOBILE USA 238   2014-11-08   

Last updated: Wed, 01 Jun 2022 03:09:23 UTC

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