Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
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Marked Tree, AR

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
870-358 A MRTRARXADS0  1722 E. RITTER TEL. CO. 528      
870-375 A LTRKAR10G01  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 528      

Last updated: Wed, 04 Mar 2026 03:00:52 UTC

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