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: 537

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-537 A Columbia MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-537 0 Columbia MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC DBA T-MOBILE USA 238   2009-10-30   
443-537 1 Columbia MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2009-10-25   
443-537 2 Columbia MD   2589 US LEC OF MARYLAND, INC. 238   2011-03-11   
443-537 3 Columbia MD   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-06-03   
443-537 4 Columbia MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2009-07-13   
443-537 5 Columbia MD   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-06-14   
443-537 6 Columbia MD   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-06-14   
443-537 7 Columbia MD   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-06-14   
443-537 8 Columbia MD   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-06-14   
443-537 9 Columbia MD   071F BANDWIDTH.COM CLEC, LLC - MD 238   2011-02-05   

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

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