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: 525

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
636-525 A Imperial MO IMPRMO58RS2  9533 SOUTHWESTERN BELL 520      
636-525 0 Imperial MO IMPRMO58RS2  9533 SOUTHWESTERN BELL 520      
636-525 1 Imperial MO STLSMO05RMD  993E BANDWIDTH.COM CLEC, LLC - MO 520   2009-01-17   
636-525 2 Imperial MO STLVMOOH6MD  6529 T-MOBILE USA, INC. 520   2022-01-09   
636-525 3 Imperial MO STLSMO09WMD  516C AT&T CORP. 520   2010-03-25   
636-525 4 Imperial MO STLVMOOH6MD  6529 T-MOBILE USA, INC. 520   2022-01-09   
636-525 5 Imperial MO STLSMOGZDS5  225F PEERLESS NETWORK OF MISSOURI, LLC - MO 520   2013-05-04   
636-525 6 Imperial MO STLSMOGZDS5  225F PEERLESS NETWORK OF MISSOURI, LLC - MO 520   2013-05-04   

Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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