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: 455

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-455 A Baltimore MD BLTMMDWLDS0  9212 VERIZON MARYLAND, INC. 238      
443-455 0 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2008-06-16   
443-455 1 Baltimore MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2009-10-12   
443-455 2 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2006-07-04   
443-455 3 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2006-07-04   
443-455 4 Baltimore MD   145J TERRA NOVA TELECOM INC. 238   2023-11-16   
443-455 5 Baltimore MD BLTMMDWLDS0  9212 VERIZON MARYLAND, INC. 238   2006-06-14   
443-455 6 Baltimore MD BLTMMDWLDS0  9212 VERIZON MARYLAND, INC. 238   2006-06-19   
443-455 7 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2006-07-04   
443-455 8 Baltimore MD BLTMMDWLDS0  9212 VERIZON MARYLAND, INC. 238   2006-06-14   
443-455 9 Baltimore MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-02-24   

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

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