Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 737 [Rate centres in NPA 737] [Dial plan for NPA 737]

NXX: 250

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
737-250 A Martindale TX SMRCTXXAYMD  903C ONVOY, LLC - TX 558      
737-250 0 Martindale TX   903C ONVOY, LLC - TX 558   2018-04-22   
737-250 1 Martindale TX   073H TELNYX LLC 558   2018-09-17   
737-250 2 Martindale TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 558   2018-04-23   
737-250 3 Martindale TX   177F PEERLESS NETWORK OF TEXAS, LLC - TX 558   2018-11-16   
737-250 5 Martindale TX   158H INVOXIO INCORPORATED 558   2018-07-29   
737-250 6 Martindale TX   903C ONVOY, LLC - TX 558   2020-08-16   
737-250 7 Martindale TX   903C ONVOY, LLC - TX 558   2020-08-16   
737-250 8 Martindale TX   903C ONVOY, LLC - TX 558   2020-08-16   
737-250 9 Martindale TX   903C ONVOY, LLC - TX 558   2020-11-23   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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