Local Calling Guide

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

NXX: 393

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-393 A Columbia MD BLTOMDXIDS0  6050 GLOBAL CROSSING LOCAL SERVICES, INC. - MD 238      
443-393 0 Columbia MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-01-08   
443-393 1 Columbia MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-01-08   
443-393 2 Columbia MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-09-10   
443-393 3 Columbia MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-09-10   
443-393 4 Columbia MD BLTOMDXIDS0  6050 GLOBAL CROSSING LOCAL SERVICES, INC. - MD 238      
443-393 5 Columbia MD BLTOMDXIDS0  6050 GLOBAL CROSSING LOCAL SERVICES, INC. - MD 238      
443-393 6 Columbia MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-05-08   
443-393 7 Columbia MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2011-04-03   
443-393 8 Columbia MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-393 9 Columbia MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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