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: 378

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-378 A Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2024-02-09   
443-378 0 Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-378 1 Baltimore MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
443-378 2 Baltimore MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
443-378 3 Baltimore MD CLMAMDJTAMD  2589 US LEC OF MARYLAND, INC. 238      
443-378 4 Baltimore MD BLTMMDCHDS2  9212 VERIZON MARYLAND, INC. 238      
443-378 5 Baltimore MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-378 6 Baltimore MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
443-378 7 Baltimore MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-378 8 Baltimore MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-378 9 Baltimore MD   876D ONVOY, LLC - MD 238      

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

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