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: 274

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
660-274 A King City MO KSCZMODR3MD  4932 LEVEL 3 COMMUNICATIONS, LLC - MO 524      
660-274 1 King City MO   5814 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MO 524   2024-10-17   
660-274 7 King City MO   508J CENTURYLINK COMMUNICATIONS, LLC 524   2013-10-31   

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

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