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: 248

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-248 A St Louis MO   128L E. RITTER COMMUNICATIONS, LLC 520   2026-02-19   
557-248 1 St Louis MO   128L E. RITTER COMMUNICATIONS, LLC 520   2026-02-19   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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