Local Calling Guide

Area code/prefix search

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

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
573-478 A PHLAMOXARS0  1914 MARK TWAIN RURAL TEL. CO. 520      

Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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