Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Simms, TX

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
430-543 A TXRKTXXANMD  903C ONVOY, LLC - TX 554      
430-543 0   073H TELNYX LLC 554   2021-04-09   
430-543 1   793K TWC IP ENABLED SERVICES, LLC 554   2023-12-10   
430-543 3   903C ONVOY, LLC - TX 554   2021-03-19   
430-543 5   903C ONVOY, LLC - TX 554   2018-12-28   
430-543 6   624H ONVOY SPECTRUM, LLC 554   2021-12-04   
430-543 7   624H ONVOY SPECTRUM, LLC 554   2021-12-04   
430-543 8   624H ONVOY SPECTRUM, LLC 554   2021-06-28   
903-543 A SMMSTXXARS0  1181 VALOR TELECOMM TX, LD-TX #2 DBA WINDSTREAM COMM SW 554      

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

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