Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 580 [Rate centres in NPA 580] [Dial plan for NPA 580]

NXX: 255

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
580-255 A Duncan OK DNCNOKMADS0  9533 SOUTHWESTERN BELL 536      

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

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