Local Calling Guide

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NPA: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

NXX: 740

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-740 A Baltimore MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-740 0 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-03-28   
443-740 1 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-03-28   
443-740 2 Baltimore MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2005-03-20   
443-740 3 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-03-28   
443-740 4 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-03-28   
443-740 5 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2005-03-28   
443-740 6 Baltimore MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2024-12-31   
443-740 7 Baltimore MD BLTQMD019MD  490J DISH WIRELESS, LLC 238   2024-07-20   
443-740 8 Baltimore MD BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2024-10-23   
443-740 9 Baltimore MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2005-08-03   

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

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