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: 253

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-253 A Kirkwood MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-07-18   
557-253 0 Kirkwood MO   093F ONVOY, LLC - MO 520   2026-07-20   
557-253 1 Kirkwood MO   093F ONVOY, LLC - MO 520   2026-07-20   
557-253 2 Kirkwood MO   093F ONVOY, LLC - MO 520   2026-07-20   
557-253 5 Kirkwood MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-07-18   
557-253 6 Kirkwood MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-07-18   
557-253 7 Kirkwood MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-07-18   
557-253 8 Kirkwood MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-07-18   
557-253 9 Kirkwood MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-07-18   

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

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