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: 657

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-657 A Randallstown MD BLTMMDDNDS2  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238      
443-657 0 Randallstown MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2014-11-08   
443-657 1 Randallstown MD   515J IP HORIZON LLC 238   2016-10-14   
443-657 2 Randallstown MD BLTMMDDNDS2  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238      
443-657 3 Randallstown MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2014-11-08   
443-657 6 Randallstown MD   145J TERRA NOVA TELECOM INC. 238   2024-02-15   
443-657 7 Randallstown MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2015-11-14   
443-657 8 Randallstown MD   876D ONVOY, LLC - MD 238   2024-02-29   
443-657 9 Randallstown MD   876D ONVOY, LLC - MD 238   2024-02-29   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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