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: 444

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-444 A Creve Coeur MO   093F ONVOY, LLC - MO 520   2025-09-08   
557-444 0 Creve Coeur MO   093F ONVOY, LLC - MO 520   2025-09-08   
557-444 1 Creve Coeur MO   093F ONVOY, LLC - MO 520   2026-03-14   
557-444 2 Creve Coeur MO   093F ONVOY, LLC - MO 520   2026-05-03   
557-444 3 Creve Coeur MO   093F ONVOY, LLC - MO 520   2026-05-03   
557-444 4 Creve Coeur MO   093F ONVOY, LLC - MO 520   2025-09-08   
557-444 5 Creve Coeur MO   093F ONVOY, LLC - MO 520   2025-09-08   
557-444 6 Creve Coeur MO   093F ONVOY, LLC - MO 520   2026-06-13   
557-444 7 Creve Coeur MO   093F ONVOY, LLC - MO 520   2026-06-13   
557-444 8 Creve Coeur MO   093F ONVOY, LLC - MO 520   2026-01-10   
557-444 9 Creve Coeur MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-12-05   

Last updated: Tue, 16 Jun 2026 00:09:45 UTC

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