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: 587

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
660-587 A La Plata MO KSCYMO55XXX  093F ONVOY, LLC - MO 524      
660-587 2 La Plata MO   4932 LEVEL 3 COMMUNICATIONS, LLC - MO 524   2016-08-27   
660-587 6 La Plata MO   093F ONVOY, LLC - MO 524   2021-01-04   
660-587 7 La Plata MO   508J CENTURYLINK COMMUNICATIONS, LLC 524   2013-10-29   
660-587 8 La Plata MO   093F ONVOY, LLC - MO 524   2021-06-19   

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

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