Local Calling Guide

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NPA: 531 [Rate centres in NPA 531] [Dial plan for NPA 531]

NXX: 531

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
531-531 A South Sioux City NE   883K AHOI LLC 630   2026-07-25   
531-531 1 South Sioux City NE   883K AHOI LLC 630   2026-07-25   

Last updated: Tue, 16 Jun 2026 00:09:45 UTC

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