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: 431

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-431 A Randallstown MD BLTMMDCHYMD  2593 CORE COMMUNICATIONS, INC.- MD 238      
443-431 0 Randallstown MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC DBA T-MOBILE USA 238   2020-04-06   
443-431 2 Randallstown MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-07-31   
443-431 3 Randallstown MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2017-11-24   
443-431 4 Randallstown MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2017-11-24   
443-431 5 Randallstown MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
443-431 6 Randallstown MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
443-431 7 Randallstown MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
443-431 8 Randallstown MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2018-10-19   
443-431 9 Randallstown MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2018-08-27   

Last updated: Fri, 13 May 2022 22:16:13 UTC

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