Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 636 [Rate centres in NPA 636] [Dial plan for NPA 636]

NXX: 434

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
636-434 A Portage des Sioux MO PRSXMO68RS0  9533 SOUTHWESTERN BELL 520      
636-434 0 Portage des Sioux MO PRSXMO68RS0  9533 SOUTHWESTERN BELL 520      
636-434 1 Portage des Sioux MO STLSMOWQDS2  093F ONVOY, LLC - MO 520   2016-03-31   
636-434 2 Portage des Sioux MO STLSMOWQDS2  093F ONVOY, LLC - MO 520   2016-03-31   
636-434 5 Portage des Sioux MO STLSMO09WMD  516C AT&T CORP. 520   2011-05-20   
636-434 9 Portage des Sioux MO STLSMO05XMX  624H ONVOY SPECTRUM, LLC 520   2025-01-11   

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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