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: 247

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-247 A Mehlville MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-01-25   
557-247 0 Mehlville MO   093F ONVOY, LLC - MO 520   2026-02-20   
557-247 1 Mehlville MO   093F ONVOY, LLC - MO 520   2026-02-20   
557-247 9 Mehlville MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-01-25   

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

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