Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 830 [Rate centres in NPA 830] [Dial plan for NPA 830]

NXX: 666

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
830-666 A Seguin TX SNANTXTSDS0  319D FOREMOST TELECOMMUNICATIONS CORPORATION - TX 566      
830-666 0 Seguin TX   6529 T-MOBILE USA, INC. 566   2022-11-02   
830-666 1 Seguin TX   6529 T-MOBILE USA, INC. 566   2022-11-02   
830-666 2 Seguin TX   6529 T-MOBILE USA, INC. 566   2022-11-02   
830-666 3 Seguin TX   6529 T-MOBILE USA, INC. 566   2022-11-02   
830-666 4 Seguin TX   6529 T-MOBILE USA, INC. 566   2022-11-02   
830-666 6 Seguin TX   319D FOREMOST TELECOMMUNICATIONS CORPORATION - TX 566   2017-12-17   
830-666 8 Seguin TX   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 566   2024-06-15   
830-666 9 Seguin TX   6529 T-MOBILE USA, INC. 566   2022-11-02   

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

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