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: 728

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
636-728 A Chesterfield MCA3 MO CHFDMO52DSA  9533 SOUTHWESTERN BELL 520      
636-728 0 Chesterfield MCA3 MO   9533 SOUTHWESTERN BELL 520      
636-728 1 Chesterfield MCA3 MO   9533 SOUTHWESTERN BELL 520      
636-728 2 Chesterfield MCA3 MO   9533 SOUTHWESTERN BELL 520      
636-728 3 Chesterfield MCA3 MO   9533 SOUTHWESTERN BELL 520      
636-728 5 Chesterfield MCA3 MO   9533 SOUTHWESTERN BELL 520      
636-728 6 Chesterfield MCA3 MO   9533 SOUTHWESTERN BELL 520      
636-728 7 Chesterfield MCA3 MO   9533 SOUTHWESTERN BELL 520      
636-728 8 Chesterfield MCA3 MO   6529 T-MOBILE USA, INC. 520   2011-07-18   
636-728 9 Chesterfield MCA3 MO   993E BANDWIDTH.COM CLEC, LLC - MO 520   2012-04-26   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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