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: 520

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
737-520 A Fentress TX SMRCTXXAYMD  903C ONVOY, LLC - TX 558      
737-520 0 Fentress TX   177F PEERLESS NETWORK OF TEXAS, LLC - TX 558   2020-05-31   
737-520 1 Fentress TX   177F PEERLESS NETWORK OF TEXAS, LLC - TX 558   2020-08-30   
737-520 2 Fentress TX   073H TELNYX LLC 558   2019-09-27   
737-520 3 Fentress TX   903C ONVOY, LLC - TX 558   2020-08-15   
737-520 4 Fentress TX   903C ONVOY, LLC - TX 558   2020-08-15   
737-520 5 Fentress TX   903C ONVOY, LLC - TX 558   2019-09-22   
737-520 6 Fentress TX   903C ONVOY, LLC - TX 558   2019-09-22   
737-520 7 Fentress TX   903C ONVOY, LLC - TX 558   2020-08-15   
737-520 8 Fentress TX   903C ONVOY, LLC - TX 558   2020-09-13   
737-520 9 Fentress TX   903C ONVOY, LLC - TX 558   2020-09-13   

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

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