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: 200

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-200 A Ladue MO STLSMOWQDS2  093F ONVOY, LLC - MO 520      
557-200 0 Ladue MO   073H TELNYX LLC 520   2022-10-10   
557-200 1 Ladue MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2022-12-02   
557-200 2 Ladue MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2022-12-02   
557-200 3 Ladue MO   093F ONVOY, LLC - MO 520   2022-12-11   
557-200 4 Ladue MO   093F ONVOY, LLC - MO 520   2022-12-11   
557-200 5 Ladue MO   093F ONVOY, LLC - MO 520   2024-07-18   
557-200 6 Ladue MO   093F ONVOY, LLC - MO 520   2022-12-11   
557-200 7 Ladue MO   093F ONVOY, LLC - MO 520   2022-10-09   
557-200 8 Ladue MO   093F ONVOY, LLC - MO 520   2022-10-09   
557-200 9 Ladue MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2022-11-22   

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

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