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: 243

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-243 A St Louis MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-11-23   
557-243 4 St Louis MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-11-23   
557-243 5 St Louis MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-11-23   
557-243 6 St Louis MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-11-23   
557-243 7 St Louis MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-11-23   
557-243 8 St Louis MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-11-23   
557-243 9 St Louis MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-11-23   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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