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: 291

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
636-291 A Washington MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-11-03   
636-291 8 Washington MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-11-06   
636-291 9 Washington MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-11-03   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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