Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 531 [Rate centres in NPA 531] [Dial plan for NPA 531]

NXX: 303

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
531-303 A Polk NE LNCLNEXLXKX  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 958      
531-303 3 Polk NE LNCLNEXLXFX  549E ONVOY, LLC - NE 958   2022-11-12   
531-303 9 Polk NE LNCLNEXLXKX  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 958   2022-11-07   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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