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: 666

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-666 A Chestertown MD SLBRMDSBXFX  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 242      
443-666 0 Chestertown MD   6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 242   2018-01-25   
443-666 1 Chestertown MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 242   2021-04-08   
443-666 2 Chestertown MD   829J PAETEC ITEL, LLC 242   2014-11-08   
443-666 3 Chestertown MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 242   2012-08-02   
443-666 4 Chestertown MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 242   2016-03-11   
443-666 5 Chestertown MD   2593 CORE COMMUNICATIONS, INC.- MD 242   2019-05-02   
443-666 6 Chestertown MD   7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 242   2014-10-20   
443-666 7 Chestertown MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 242   2018-08-27   
443-666 8 Chestertown MD   073H TELNYX LLC 242   2017-09-13   
443-666 9 Chestertown MD   5562 METROPCS, INC. 242   2021-05-10   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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