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: 539

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-539 A Columbia MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2025-04-01   
443-539 0 Columbia MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-539 1 Columbia MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-539 2 Columbia MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-539 3 Columbia MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      
443-539 4 Columbia MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2006-08-15   
443-539 5 Columbia MD BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2008-10-01   
443-539 6 Columbia MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-10-28   
443-539 7 Columbia MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2010-02-15   
443-539 8 Columbia MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2008-02-13   
443-539 9 Columbia MD PIVLMDPKXEX  829J PAETEC ITEL, LLC 238      

Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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