Local Calling Guide

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NPA: 956 [Rate centres in NPA 956] [Dial plan for NPA 956]

NXX: 481

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
956-481 A San Isidro TX SISDTXXARS0  2159 VALLEY TEL. COOP., INC. 568      

Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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