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: 507

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-507 A St Louis MO STLSMO05XMX  624H ONVOY SPECTRUM, LLC 520      
557-507 0 St Louis MO   624H ONVOY SPECTRUM, LLC 520   2023-10-20   
557-507 1 St Louis MO   624H ONVOY SPECTRUM, LLC 520   2023-10-20   
557-507 2 St Louis MO   624H ONVOY SPECTRUM, LLC 520   2023-10-20   
557-507 3 St Louis MO   624H ONVOY SPECTRUM, LLC 520   2023-10-20   
557-507 4 St Louis MO   624H ONVOY SPECTRUM, LLC 520   2023-10-20   
557-507 5 St Louis MO   624H ONVOY SPECTRUM, LLC 520   2023-10-20   
557-507 6 St Louis MO   624H ONVOY SPECTRUM, LLC 520   2023-10-20   
557-507 7 St Louis MO   624H ONVOY SPECTRUM, LLC 520   2023-10-20   
557-507 8 St Louis MO   624H ONVOY SPECTRUM, LLC 520   2023-10-20   
557-507 9 St Louis MO   624H ONVOY SPECTRUM, LLC 520   2023-10-20   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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