Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 903 [Rate centres in NPA 903] [Dial plan for NPA 903]

NXX: 623

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
903-623 A Windom TX WNDMTXXADS0  2154 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
903-623 0 Windom TX   135H PEOPLES COMMUNICATION, INC. -TX 552   2013-12-01   
903-623 1 Windom TX   903C ONVOY, LLC - TX 552   2016-04-14   
903-623 2 Windom TX   145J TERRA NOVA TELECOM INC. 552   2024-08-22   
903-623 3 Windom TX   073H TELNYX LLC 552   2019-05-17   
903-623 4 Windom TX   2154 FRONTIER SOUTHWEST INC DBA FRONTIER COMM OF TEXAS 552      
903-623 5 Windom TX   004F BANDWIDTH.COM CLEC, LLC - TX 552   2011-12-24   
903-623 6 Windom TX   903C ONVOY, LLC - TX 552   2012-07-06   
903-623 7 Windom TX   903C ONVOY, LLC - TX 552   2009-03-08   
903-623 8 Windom TX   903C ONVOY, LLC - TX 552   2012-12-13   
903-623 9 Windom TX   903C ONVOY, LLC - TX 552   2016-04-14   

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

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