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: 957

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-957 A Baltimore MD BLTMMDCHXAX  7421 AT&T - LOCAL 238      
443-957 1 Baltimore MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-957 2 Baltimore MD BLTMMDCHXAX  7421 AT&T - LOCAL 238      
443-957 4 Baltimore MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-957 5 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-957 6 Baltimore MD BLTMMDCHXAX  7421 AT&T - LOCAL 238      
443-957 7 Baltimore MD   145J TERRA NOVA TELECOM INC. 238      
443-957 9 Baltimore MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

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