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: 557

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-557 A Glen Burnie MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-557 0 Glen Burnie MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-557 1 Glen Burnie MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-557 2 Glen Burnie MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-557 3 Glen Burnie MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-02-29   
443-557 4 Glen Burnie MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-557 5 Glen Burnie MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-557 6 Glen Burnie MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-557 7 Glen Burnie MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-557 8 Glen Burnie MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2007-06-16   
443-557 9 Glen Burnie MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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