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: 212

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-212 A Mehlville MO   6529 T-MOBILE USA, INC. 520      
557-212 0 Mehlville MO   093F ONVOY, LLC - MO 520   2025-05-12   
557-212 1 Mehlville MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-05-21   
557-212 2 Mehlville MO   093F ONVOY, LLC - MO 520   2025-05-12   
557-212 3 Mehlville MO   6529 T-MOBILE USA, INC. 520   2025-08-14   
557-212 4 Mehlville MO   515J IP HORIZON LLC 520   2023-12-07   
557-212 5 Mehlville MO   515J IP HORIZON LLC 520   2023-12-07   
557-212 6 Mehlville MO   093F ONVOY, LLC - MO 520   2024-04-04   
557-212 7 Mehlville MO   093F ONVOY, LLC - MO 520   2024-02-26   
557-212 8 Mehlville MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2024-02-22   
557-212 9 Mehlville MO   624H ONVOY SPECTRUM, LLC 520   2024-12-05   

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

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