Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 660 [Rate centres in NPA 660] [Dial plan for NPA 660]

NXX: 331

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
660-331 A Clinton MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 524      
660-331 0 Clinton MO WRBGMOXAXCX  093F ONVOY, LLC - MO 524   2026-05-30   
660-331 7 Clinton MO MAVLMOXAX0X  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 524   2026-07-10   
660-331 8 Clinton MO MAVLMOXAX0X  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 524   2026-07-03   

Last updated: Tue, 01 Sep 2026 00:40:05 UTC

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