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: 348

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-348 A Washington Zone 11 MD WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-348 0 Washington Zone 11 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-24   
301-348 1 Washington Zone 11 MD WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-348 2 Washington Zone 11 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-348 3 Washington Zone 11 MD WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236      
301-348 4 Washington Zone 11 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-348 5 Washington Zone 11 MD WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2017-08-03   
301-348 6 Washington Zone 11 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2012-08-26   
301-348 7 Washington Zone 11 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-07-30   
301-348 8 Washington Zone 11 MD ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2016-02-24   
301-348 9 Washington Zone 11 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-24   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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