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.
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NPA: 423 [Rate centres in NPA 423] [Dial plan for NPA 423]

NXX: 866

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-866 A Niota TN KNVLTNMAYHX  318J COMCAST IP PHONE, LLC 474      
423-866 0 Niota TN KNVLTNMA49Z  525E ONVOY, LLC - TN 474   2023-09-22   
423-866 1 Niota TN KNVLTNMAYHX  318J COMCAST IP PHONE, LLC 474   2023-09-21   

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

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