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: 333

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-333 A Sappington MO   093F ONVOY, LLC - MO 520   2025-09-08   
557-333 0 Sappington MO   093F ONVOY, LLC - MO 520   2025-09-08   
557-333 3 Sappington MO   093F ONVOY, LLC - MO 520   2025-09-08   
557-333 4 Sappington MO   093F ONVOY, LLC - MO 520   2025-09-08   

Last updated: Fri, 25 Jul 2025 03:21:23 UTC

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