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: 874

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
636-874 A O'Fallon MO STLSMOGZHMD  516J TON80 COMMUNICATIONS, LLC 520      
636-874 0 O'Fallon MO   093F ONVOY, LLC - MO 520   2025-11-28   
636-874 2 O'Fallon MO STLSMOGZHMD  516J TON80 COMMUNICATIONS, LLC 520   2022-04-18   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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