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   
557-249 4 Ladue MO   7218 TELEPORT COMMUNICATIONS AMERICA, LLC - MO 520   2026-03-23   
557-249 7 Ladue MO   093F ONVOY, LLC - MO 520   2026-03-22   
557-249 8 Ladue MO   093F ONVOY, LLC - MO 520   2026-03-09   
557-249 9 Ladue MO   093F ONVOY, LLC - MO 520   2026-03-22   

Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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