Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: STLSMOGZUMD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
557-204 A St Louis MO 598J FIVE9, INC. 520      
557-204 0 St Louis MO 598J FIVE9, INC. 520   2023-07-06   

Last updated: Tue, 07 Oct 2025 16:47:53 UTC

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