Local Calling Guide

Area code/prefix search

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

NXX: 220

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
956-220 A Laredo TX SNANTX91X7Y  4290 STPCS JOINT VENTURE, LLC 566      

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

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