Local Calling Guide

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

NXX:

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-238 A Washington Zone 16 MD TMHLMDTHDS0  9212 VERIZON MARYLAND, INC. 236      
301-238 0 Washington Zone 16 MD   9212 VERIZON MARYLAND, INC. 236   2001-12-21   
301-238 1 Washington Zone 16 MD   9212 VERIZON MARYLAND, INC. 236   2004-07-10   
301-238 2 Washington Zone 16 MD   9212 VERIZON MARYLAND, INC. 236      
301-238 3 Washington Zone 16 MD   9212 VERIZON MARYLAND, INC. 236      
301-238 4 Washington Zone 16 MD   4716 PAETEC COMMUNICATIONS, INC. - MD 236   2005-02-08   
301-238 5 Washington Zone 16 MD   4716 PAETEC COMMUNICATIONS, INC. - MD 236   2007-02-23   
301-238 6 Washington Zone 16 MD   2593 CORE COMMUNICATIONS, INC. - MD 236   2019-03-29   
301-238 7 Washington Zone 16 MD   876D ONVOY, LLC - MD 236   2016-03-30   
301-238 8 Washington Zone 16 MD   876D ONVOY, LLC - MD 236   2016-03-30   

Last updated: Thu, 10 Sep 2020 02:15:24 UTC

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