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: 470

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
636-470 A O'Fallon MO   0051 SHELCOMM 520   2026-07-04   

Last updated: Sun, 17 May 2026 03:26:51 UTC

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