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: 623

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
660-623 A Tarkio MO MAVLMOXAX0X  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 524      
660-623 0 Tarkio MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 524      
660-623 1 Tarkio MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 524   2008-01-17   
660-623 6 Tarkio MO   454H MIDWEST DATA CENTER, INC. - MO 524   2015-04-16   
660-623 8 Tarkio MO   4932 LEVEL 3 COMMUNICATIONS, LLC - MO 524   2022-02-18   
660-623 9 Tarkio MO   5814 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MO 524   2007-01-24   

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

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