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: 258

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
737-258 A Milano TX AUSTTXGR09Z  7138 TELEPORT COMMUNICATIONS AMERICA, LLC - TX 558      
737-258 0 Milano TX   490J DISH WIRELESS, LLC 558   2024-01-13   
737-258 2 Milano TX   903C ONVOY, LLC - TX 558   2019-10-11   
737-258 3 Milano TX   903C ONVOY, LLC - TX 558   2020-08-16   
737-258 4 Milano TX   903C ONVOY, LLC - TX 558   2020-08-16   
737-258 5 Milano TX   903C ONVOY, LLC - TX 558   2020-08-16   
737-258 6 Milano TX   7138 TELEPORT COMMUNICATIONS AMERICA, LLC - TX 558   2019-09-26   
737-258 7 Milano TX   903C ONVOY, LLC - TX 558   2020-09-13   
737-258 8 Milano TX   903C ONVOY, LLC - TX 558   2020-09-13   
737-258 9 Milano TX   903C ONVOY, LLC - TX 558   2020-09-13   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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