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 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 9 Creve Coeur MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-12-05   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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