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: 321

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-321 A Washington Zone 11 MD VINNVACBDS0  876D ONVOY, LLC - MD 236      
301-321 0 Washington Zone 11 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-06-16   
301-321 1 Washington Zone 11 MD SLSPMD913MD  939H COMMIO, LLC 236   2021-08-29   
301-321 2 Washington Zone 11 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-06-16   
301-321 3 Washington Zone 11 MD HRNDVACKBMD  5977 BROADVIEW NETWORKS, INC. - DC 236   2014-06-09   
301-321 4 Washington Zone 11 MD WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2016-09-01   
301-321 5 Washington Zone 11 MD RKVLMDMRDS0  9212 VERIZON MARYLAND, INC. 236   2005-12-12   
301-321 6 Washington Zone 11 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-06-16   
301-321 7 Washington Zone 11 MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2016-01-07   
301-321 8 Washington Zone 11 MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2016-01-07   
301-321 9 Washington Zone 11 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-24   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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