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: 273

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
660-273 A Armstrong MO ARMSMOCRRS0  9533 SOUTHWESTERN BELL 524      
660-273 0 Armstrong MO   993E BANDWIDTH.COM CLEC, LLC - MO 524   2009-02-13   
660-273 1 Armstrong MO   9533 SOUTHWESTERN BELL 524      
660-273 2 Armstrong MO   9533 SOUTHWESTERN BELL 524      
660-273 3 Armstrong MO   225F PEERLESS NETWORK OF MISSOURI, LLC - MO 524   2014-04-10   
660-273 4 Armstrong MO   093F ONVOY, LLC - MO 524   2021-07-23   
660-273 5 Armstrong MO   225F PEERLESS NETWORK OF MISSOURI, LLC - MO 524   2025-02-27   
660-273 7 Armstrong MO   508J CENTURYLINK COMMUNICATIONS, LLC 524   2014-05-07   
660-273 8 Armstrong MO   073H TELNYX LLC 524   2019-09-30   
660-273 9 Armstrong MO   9533 SOUTHWESTERN BELL 524      

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

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