Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 956 [Rate centres in NPA 956] [Dial plan for NPA 956]

NXX: 819

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
956-819 A Laredo TX   903C ONVOY, LLC - TX 566   2025-12-07   
956-819 0 Laredo TX   903C ONVOY, LLC - TX 566   2025-12-07   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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