Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 331 [Rate centres in NPA 331] [Dial plan for NPA 331]

NXX: 325

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-325 A Lemont IL CHCGILIDXDX  624H ONVOY SPECTRUM, LLC 358   2024-05-24   
331-325 0 Lemont IL CHCGILIDXDX  624H ONVOY SPECTRUM, LLC 358   2024-05-24   
331-325 1 Lemont IL CHCGIL24DS6  224C ONVOY, LLC 358   2024-06-07   
331-325 2 Lemont IL CHCGILWUXMD  490J DISH WIRELESS, LLC 358   2024-11-21   
331-325 4 Lemont IL CHCGILWUXMD  490J DISH WIRELESS, LLC 358   2025-04-14   

Last updated: Fri, 25 Jul 2025 03:21:23 UTC

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