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: 228

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
274-228 A Sheboygan WI MILXWIJIGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 356   2025-06-29   
274-228 0 Sheboygan WI MILXWIILCMD  6508 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WI 356   2025-11-19   
274-228 9 Sheboygan WI MILXWIJIGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 356   2025-06-29   

Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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