Local Calling Guide

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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   2005-03-12   
443-957 2 Baltimore MD BLTMMDCHXAX  7421 AT&T - LOCAL 238      
443-957 4 Baltimore MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2004-05-29   
443-957 5 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-09-22   
443-957 6 Baltimore MD BLTMMDCHXAX  7421 AT&T - LOCAL 238      
443-957 9 Baltimore MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2005-08-03   

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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