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: 723

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
636-723 A St Charles MO STCHMO63DSA  9533 SOUTHWESTERN BELL 520      
636-723 0 St Charles MO   9533 SOUTHWESTERN BELL 520      
636-723 1 St Charles MO   9533 SOUTHWESTERN BELL 520      
636-723 2 St Charles MO   9533 SOUTHWESTERN BELL 520      
636-723 3 St Charles MO   145J TERRA NOVA TELECOM INC. 520   2021-01-20   
636-723 4 St Charles MO   145J TERRA NOVA TELECOM INC. 520   2021-09-26   
636-723 6 St Charles MO   515J IP HORIZON LLC 520   2013-12-19   
636-723 8 St Charles MO   508J CENTURYLINK COMMUNICATIONS, LLC 520   2013-11-30   
636-723 9 St Charles MO   093F ONVOY, LLC - MO 520   2021-11-20   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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