Local Calling Guide

Area code/prefix search

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NPA: 573 [Rate centres in NPA 573] [Dial plan for NPA 573]

NXX: 439

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
573-439 A Philadelphia MO PHLAMOXARS0  1914 MARK TWAIN RURAL TEL. CO. 520      

Last updated: Wed, 04 Mar 2026 03:00:52 UTC

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