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: 636

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
580-636 A Altus OK   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 536      
580-636 5 Altus OK   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 536   2025-08-08   
580-636 6 Altus OK   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 536   2025-10-17   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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