Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 256 [Rate centres in NPA 256] [Dial plan for NPA 256]

NXX: 423

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
256-423 A Ardmore (Limestone) AL ARMRALXADS0  0280 ARDMORE TEL. CO., INC. 470      

Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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