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: 975

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
660-975 A La Monte MO KSCYMO55XXX  093F ONVOY, LLC - MO 524      
660-975 0 La Monte MO   624H ONVOY SPECTRUM, LLC 524   2024-03-20   
660-975 1 La Monte MO   792K CHARTER IP ENABLED SERVICES, LLC 524   2024-09-01   
660-975 5 La Monte MO   516C AT&T CORP. 524   2011-06-01   
660-975 8 La Monte MO   093F ONVOY, LLC - MO 524   2019-01-13   
660-975 9 La Monte MO   093F ONVOY, LLC - MO 524   2019-01-13   

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

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