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: 355

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-355 A Ellicott City MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-355 0 Ellicott City MD BLTMMDCHX7X  073H TELNYX LLC 238   2017-03-14   
443-355 1 Ellicott City MD BLTMMDCH40Z  5562 METROPCS, INC. 238   2017-01-19   
443-355 2 Ellicott City MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
443-355 3 Ellicott City MD BLTMMDCH40Z  5562 METROPCS, INC. 238   2017-01-19   
443-355 4 Ellicott City MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-355 5 Ellicott City MD BLTMMDCH40Z  5562 METROPCS, INC. 238   2017-03-25   
443-355 6 Ellicott City MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2017-05-29   
443-355 7 Ellicott City MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2017-05-29   
443-355 8 Ellicott City MD BLTMMDCH40Z  5562 METROPCS, INC. 238   2017-10-14   
443-355 9 Ellicott City MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2017-10-20   

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

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