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: 242

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
660-242 A Montrose MO KSCZMODR3MD  4932 LEVEL 3 COMMUNICATIONS, LLC - MO 524      
660-242 2 Montrose MO   093F ONVOY, LLC - MO 524   2018-10-28   
660-242 4 Montrose MO   4932 LEVEL 3 COMMUNICATIONS, LLC - MO 524      
660-242 5 Montrose MO   093F ONVOY, LLC - MO 524   2021-02-28   
660-242 6 Montrose MO   093F ONVOY, LLC - MO 524   2021-02-28   
660-242 7 Montrose MO   093F ONVOY, LLC - MO 524   2021-02-28   
660-242 8 Montrose MO   093F ONVOY, LLC - MO 524   2021-02-28   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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