Local Calling Guide

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Search area code/prefix (NPA/NXX)
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NPA: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

NXX: 539

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-539 A Columbia MD CLMAMDJTAMD  2589 US LEC OF MARYLAND, INC. 238      
443-539 0 Columbia MD   2589 US LEC OF MARYLAND, INC. 238      
443-539 1 Columbia MD   2589 US LEC OF MARYLAND, INC. 238      
443-539 2 Columbia MD   2589 US LEC OF MARYLAND, INC. 238      
443-539 3 Columbia MD   2589 US LEC OF MARYLAND, INC. 238      
443-539 4 Columbia MD   4716 PAETEC COMMUNICATIONS, INC. - MD 238   2006-08-15   
443-539 5 Columbia MD   7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2008-10-01   
443-539 6 Columbia MD   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-10-28   
443-539 7 Columbia MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2010-02-15   
443-539 8 Columbia MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2008-02-13   
443-539 9 Columbia MD   2589 US LEC OF MARYLAND, INC. 238      

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

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