Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 301 [Rate centres in NPA 301] [Dial plan for NPA 301]

NXX: 637

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-637 A Washington Zone 10 MD MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236      
301-637 0 Washington Zone 10 MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2004-12-13   
301-637 1 Washington Zone 10 MD   2697 CTC COMMUNICATIONS CORP. - MD 236   2005-12-15   
301-637 2 Washington Zone 10 MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2006-04-07   
301-637 3 Washington Zone 10 MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2006-04-07   
301-637 4 Washington Zone 10 MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236      
301-637 5 Washington Zone 10 MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2005-04-03   
301-637 6 Washington Zone 10 MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2005-04-03   
301-637 7 Washington Zone 10 MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2005-04-03   
301-637 8 Washington Zone 10 MD   6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2006-06-17   
301-637 9 Washington Zone 10 MD   318J COMCAST IP PHONE LLC 236   2010-10-11   

Last updated: Sun, 04 Apr 2021 19:28:27 UTC

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