Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 531 [Rate centres in NPA 531] [Dial plan for NPA 531]

NXX: 413

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
531-413 A Humboldt NE   6263 UNITED STATES CELLULAR - NE 958   2025-07-19   

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

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