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: 404

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
660-404 A Leonard MO KSCYMO55XDY  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 524      
660-404 0 Leonard MO   145J TERRA NOVA TELECOM INC. 524   2025-10-09   
660-404 9 Leonard MO KSCYMO55XDY  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 524   2021-06-19   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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