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: 817 [Rate centres in NPA 817] [Dial plan for NPA 817]

NXX: 623

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
817-623 A Keller TX   903C ONVOY, LLC - TX 552      
817-623 0 Keller TX   903C ONVOY, LLC - TX 552      
817-623 1 Keller TX   903C ONVOY, LLC - TX 552      
817-623 2 Keller TX   903C ONVOY, LLC - TX 552      
817-623 3 Keller TX   903C ONVOY, LLC - TX 552      
817-623 4 Keller TX   903C ONVOY, LLC - TX 552   2022-09-26   
817-623 5 Keller TX   903C ONVOY, LLC - TX 552   2022-09-26   
817-623 6 Keller TX   903C ONVOY, LLC - TX 552      
817-623 7 Keller TX   478J NUSO, LLC 552   2023-11-26   
817-623 8 Keller TX   903C ONVOY, LLC - TX 552      
817-623 9 Keller TX   073H TELNYX LLC 552   2017-06-12   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

Sponsored by: Callcentric - VoIP Internet phone service

Like this site? We accept donations via PayPal.