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: 545

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-545 A Columbia MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-545 0 Columbia MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-09-25   
443-545 1 Columbia MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-545 2 Columbia MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-545 3 Columbia MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-545 4 Columbia MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2008-04-04   
443-545 5 Columbia MD BLTMMDCHXFX  318J COMCAST IP PHONE LLC 238   2006-06-03   
443-545 6 Columbia MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2008-08-01   
443-545 7 Columbia MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-03-03   
443-545 8 Columbia MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2016-09-19   
443-545 9 Columbia MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2008-10-03   

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

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