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: 423

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-423 A Baltimore MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-423 0 Baltimore MD HNVAMDBHAMD  3910 CAVALIER TELEPHONE MID-ATLANTIC, LLC - MD 238   2005-10-12   
443-423 1 Baltimore MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-423 2 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-01-27   
443-423 3 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-01-27   
443-423 4 Baltimore MD BLTMMDCHDS2  9212 VERIZON MARYLAND, INC. 238   2003-09-06   
443-423 5 Baltimore MD BLTMMDCHDS2  9212 VERIZON MARYLAND, INC. 238   2003-09-06   
443-423 6 Baltimore MD BLTMMDCHDS2  9212 VERIZON MARYLAND, INC. 238   2003-09-06   
443-423 7 Baltimore MD BLTMMDCHDS2  9212 VERIZON MARYLAND, INC. 238   2003-09-06   
443-423 8 Baltimore MD BLTMMDCHDS3  9212 VERIZON MARYLAND, INC. 238   2004-06-04   
443-423 9 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-01-27   

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

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