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: 816

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
660-816 A Downing MO KSCYMO55XXX  093F ONVOY, LLC - MO 524      
660-816 0 Downing MO   624H ONVOY SPECTRUM, LLC 524   2025-01-12   
660-816 8 Downing MO   093F ONVOY, LLC - MO 524   2021-01-06   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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