Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 972 [Rate centres in NPA 972] [Dial plan for NPA 972]

NXX: 531

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
972-531 A Plano TX DLLSTXRIXPZ  7421 AT&T - LOCAL 552      

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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