Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 557 [Rate centres in NPA 557] [Dial plan for NPA 557]

NXX: 249

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-249 A Ladue MO   093F ONVOY, LLC - MO 520   2026-03-06   
557-249 0 Ladue MO   093F ONVOY, LLC - MO 520   2026-03-06   
557-249 1 Ladue MO   093F ONVOY, LLC - MO 520   2026-03-06   

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

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