Local Calling Guide

Area code/prefix search

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

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
636-666 6   145J TERRA NOVA TELECOM INC. 520   2019-02-22   
636-666 7 STLSMOWQDS2  093F ONVOY, LLC - MO 520   2023-10-22   
636-666 8 STLSMOWQDS2  093F ONVOY, LLC - MO 520   2024-03-03   
636-666 9 STLSMOWQDS2  093F ONVOY, LLC - MO 520   2024-07-05   

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Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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