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: 448

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-448 A Denton MD SLBRMDSBXLX  318J COMCAST IP PHONE, LLC 242      
443-448 1 Denton MD SLBRMDSBXVX  876D ONVOY, LLC - MD 242   2021-03-05   
443-448 2 Denton MD SLBRMDSBX0X  624H ONVOY SPECTRUM, LLC 242   2021-12-09   
443-448 3 Denton MD ESTNMDES5MD  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 242   2015-11-02   
443-448 4 Denton MD SLBRMDSBXLX  318J COMCAST IP PHONE, LLC 242   2006-07-31   
443-448 5 Denton MD SLBRMDSBXFX  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 242   2016-10-16   
443-448 6 Denton MD SLBRMDSBXUX  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 242   2014-06-25   
443-448 7 Denton MD SLBRMDSBXLX  318J COMCAST IP PHONE, LLC 242   2015-03-20   
443-448 8 Denton MD SLBRMDSBXVX  876D ONVOY, LLC - MD 242   2017-04-13   
443-448 9 Denton MD SLBRMD902MD  073H TELNYX LLC 242   2017-09-13   

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

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