Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

NXX: 233

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-233 A Vienna MD   829J PAETEC ITEL, LLC 242   2025-04-01   
443-233 0 Vienna MD SLBRMDSBXVX  876D ONVOY, LLC - MD 242   2020-08-09   
443-233 1 Vienna MD SLBRMDSBXVX  876D ONVOY, LLC - MD 242   2020-08-09   
443-233 2 Vienna MD SLBRMDSBXLX  318J COMCAST IP PHONE, LLC 242   2007-08-08   
443-233 3 Vienna MD   2593 CORE COMMUNICATIONS, INC.- MD 242   2018-06-17   
443-233 4 Vienna MD   145J TERRA NOVA TELECOM INC. 242   2022-04-23   
443-233 5 Vienna MD SLBRMDSBXVX  876D ONVOY, LLC - MD 242   2020-10-17   
443-233 6 Vienna MD SLBRMDSBXFX  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 242   2012-05-26   
443-233 7 Vienna MD   2593 CORE COMMUNICATIONS, INC.- MD 242   2018-06-17   
443-233 8 Vienna MD SLBRMD902MD  073H TELNYX LLC 242   2017-09-13   
443-233 9 Vienna MD   829J PAETEC ITEL, LLC 242      

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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