Local Calling Guide

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Mount Sterling, MO

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
573-943 A MTSTMOXADS0  9787 BRIGHTSPEED OF MISSOURI, LLC 521      
573-943 0   093F ONVOY, LLC - MO 521   2019-11-29   
573-943 1   073H TELNYX LLC 521   2020-08-02   
573-943 2   9787 BRIGHTSPEED OF MISSOURI, LLC 521      
573-943 3   4932 LEVEL 3 COMMUNICATIONS, LLC - MO 521   2013-08-26   
573-943 4   093F ONVOY, LLC - MO 521   2018-07-16   
573-943 5   093F ONVOY, LLC - MO 521   2021-03-06   
573-943 6   9787 BRIGHTSPEED OF MISSOURI, LLC 521      
573-943 8   624H ONVOY SPECTRUM, LLC 521   2024-03-05   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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