Local Calling Guide

Area code/prefix search

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

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
573-853 A PHLAMOXARS0  1914 MARK TWAIN RURAL TEL. CO. 520      

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

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