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: 251

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-251 A Kirkwood MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-04-12   
557-251 0 Kirkwood MO   093F ONVOY, LLC - MO 520   2026-04-13   
557-251 2 Kirkwood MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-04-12   
557-251 3 Kirkwood MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-04-12   
557-251 4 Kirkwood MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-04-12   
557-251 5 Kirkwood MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-04-12   
557-251 6 Kirkwood MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-04-12   
557-251 7 Kirkwood MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-04-12   
557-251 8 Kirkwood MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-04-12   
557-251 9 Kirkwood MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2026-04-12   

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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