Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Patterson, MO

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
573-856 A PASNMOXXRS0  1885 WINDSTREAM MISSOURI, INC. 520      
573-856 0   1885 WINDSTREAM MISSOURI, INC. 520      
573-856 1   624H ONVOY SPECTRUM, LLC 520   2025-01-11   
573-856 3   993E BANDWIDTH.COM CLEC, LLC - MO 520   2017-10-16   
573-856 4   1885 WINDSTREAM MISSOURI, INC. 520      
573-856 5   093F ONVOY, LLC - MO 520   2021-07-24   
573-856 9   1885 WINDSTREAM MISSOURI, INC. 520   2020-02-17   

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

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