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: 237

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-237 A Ladue MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-07-07   
557-237 7 Ladue MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-07-07   
557-237 8 Ladue MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-07-07   
557-237 9 Ladue MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-07-07   

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

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