Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

NPA: 301 [Rate centres in NPA 301] [Dial plan for NPA 301]

NXX: 823

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-823 A Washington Zone 13 MD WASHDCDTDS1  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-823 0 Washington Zone 13 MD   876D ONVOY, LLC - MD 236   2025-02-01   
301-823 1 Washington Zone 13 MD   876D ONVOY, LLC - MD 236   2025-02-01   
301-823 2 Washington Zone 13 MD WASHDCDTDS1  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236   2008-10-10   
301-823 3 Washington Zone 13 MD   829J PAETEC ITEL, LLC 236   2012-11-21   
301-823 4 Washington Zone 13 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-06-16   
301-823 5 Washington Zone 13 MD WASHDC125MD  197D VONAGE AMERICA LLC 236   2020-05-20   
301-823 6 Washington Zone 13 MD   876D ONVOY, LLC - MD 236   2025-03-09   
301-823 7 Washington Zone 13 MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-823 8 Washington Zone 13 MD LARLMDCCDS0  4492 VDL, INC. DBA GLOBAL TELECOM BROKERS - MD 236   2004-04-06   
301-823 9 Washington Zone 13 MD WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2021-11-08   

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

Sponsored by: FiberConX Communications Ltd.

Like this site? We accept donations via PayPal.