Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 274 [Rate centres in NPA 274] [Dial plan for NPA 274]

NXX: 203

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
274-203 A Algoma WI   6529 T-MOBILE USA, INC. 350   2025-03-01   
274-203 0 Algoma WI   5562 METROPCS, INC. 350   2025-03-30   
274-203 8 Algoma WI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 350   2026-04-05   
274-203 9 Algoma WI   6529 T-MOBILE USA, INC. 350   2025-03-01   

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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