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: 250

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-250 A St Louis MO   671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 520   2026-04-28   
557-250 3 St Louis MO   671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 520   2026-04-28   

Last updated: Wed, 04 Mar 2026 03:00:52 UTC

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