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: 228

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-228 A St Louis MO STLTMOBOAMD  5814 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MO 520   2025-01-26   
557-228 0 St Louis MO STLTMOBOAMD  5814 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MO 520   2025-01-26   
557-228 1 St Louis MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-09-24   
557-228 2 St Louis MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-09-22   
557-228 3 St Louis MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-09-22   
557-228 4 St Louis MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-09-22   
557-228 5 St Louis MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-09-22   
557-228 6 St Louis MO   093F ONVOY, LLC - MO 520   2025-02-01   
557-228 7 St Louis MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-03-13   
557-228 8 St Louis MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-03-13   
557-228 9 St Louis MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 520   2025-03-13   

Last updated: Sun, 17 May 2026 03:26:51 UTC

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