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: 203

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-203 A Mehlville MO STLVMOOH6MD  5562 METROPCS, INC. 520      
557-203 0 Mehlville MO STLSMOWQDS2  093F ONVOY, LLC - MO 520   2023-08-10   
557-203 1 Mehlville MO STLSMOWQDS2  093F ONVOY, LLC - MO 520   2023-08-10   
557-203 2 Mehlville MO STLSMOWQDS2  093F ONVOY, LLC - MO 520   2023-07-09   
557-203 3 Mehlville MO STLSMOWQDS2  093F ONVOY, LLC - MO 520   2023-07-09   
557-203 4 Mehlville MO STLSMOWQDS2  093F ONVOY, LLC - MO 520   2023-07-09   
557-203 5 Mehlville MO STLSMOWQDS2  093F ONVOY, LLC - MO 520   2023-08-10   
557-203 6 Mehlville MO NWTPMOABGT1  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2023-09-04   
557-203 7 Mehlville MO   6529 T-MOBILE USA, INC. 520   2025-05-30   
557-203 8 Mehlville MO STLVMOOH6MD  5562 METROPCS, INC. 520   2023-07-03   
557-203 9 Mehlville MO STLVMOOH6MD  5562 METROPCS, INC. 520   2023-07-03   

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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