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: 241

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-241 A Ladue MO   093F ONVOY, LLC - MO 520   2025-11-15   
557-241 0 Ladue MO   093F ONVOY, LLC - MO 520   2025-11-15   
557-241 1 Ladue MO   093F ONVOY, LLC - MO 520   2025-11-15   
557-241 2 Ladue MO   093F ONVOY, LLC - MO 520   2025-11-15   
557-241 3 Ladue MO   093F ONVOY, LLC - MO 520   2025-11-15   
557-241 4 Ladue MO   093F ONVOY, LLC - MO 520   2025-11-15   
557-241 8 Ladue MO   093F ONVOY, LLC - MO 520   2025-11-17   
557-241 9 Ladue MO   093F ONVOY, LLC - MO 520   2025-11-17   

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

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