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: 208

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-208 A Ladue MO STLSMOWQDS2  093F ONVOY, LLC - MO 520      
557-208 0 Ladue MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2023-11-12   
557-208 1 Ladue MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2023-11-12   
557-208 2 Ladue MO   093F ONVOY, LLC - MO 520   2023-11-11   
557-208 3 Ladue MO   093F ONVOY, LLC - MO 520   2023-11-11   
557-208 4 Ladue MO   093F ONVOY, LLC - MO 520   2023-11-11   
557-208 5 Ladue MO   093F ONVOY, LLC - MO 520   2023-11-11   
557-208 6 Ladue MO   624H ONVOY SPECTRUM, LLC 520   2023-11-27   
557-208 7 Ladue MO   624H ONVOY SPECTRUM, LLC 520   2023-11-27   
557-208 8 Ladue MO   624H ONVOY SPECTRUM, LLC 520   2023-11-27   
557-208 9 Ladue MO   624H ONVOY SPECTRUM, LLC 520   2023-11-27   

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

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