Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 512 [Rate centres in NPA 512] [Dial plan for NPA 512]

NXX: 255

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
512-255 A Austin TX AUSTTXRRDS0  9533 SOUTHWESTERN BELL 558      

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

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