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: 256

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-256 A North East MD   829J PAETEC ITEL, LLC 238   2025-04-01   
443-256 0 North East MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2019-07-14   
443-256 1 North East MD   829J PAETEC ITEL, LLC 238      
443-256 2 North East MD BLTMMDCH40Z  5562 METROPCS, INC. 238   2019-03-31   
443-256 3 North East MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2014-06-15   
443-256 4 North East MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2014-09-20   
443-256 5 North East MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2014-09-20   
443-256 6 North East MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2014-11-03   
443-256 7 North East MD BLTMMDDN2MD  508J CENTURYLINK COMMUNICATIONS, LLC 238   2014-06-25   
443-256 8 North East MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2014-10-01   
443-256 9 North East MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2014-11-03   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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