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: 239

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-239 A St Louis MO   7218 TELEPORT COMMUNICATIONS AMERICA, LLC - MO 520   2025-08-29   
557-239 6 St Louis MO   7218 TELEPORT COMMUNICATIONS AMERICA, LLC - MO 520   2025-08-29   

Last updated: Tue, 15 Jul 2025 18:46:49 UTC

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