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: 265

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-265 A St Louis MO   093F ONVOY, LLC - MO 520   2026-11-12   
557-265 0 St Louis MO   093F ONVOY, LLC - MO 520   2026-11-12   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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