Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 414 [Rate centres in NPA 414] [Dial plan for NPA 414]

NXX: 521

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
414-521 A Milwaukee Zone 1 WI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 356   2026-01-19   
414-521 7 Milwaukee Zone 1 WI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 356   2026-01-19   
414-521 8 Milwaukee Zone 1 WI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 356   2026-01-19   
414-521 9 Milwaukee Zone 1 WI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 356   2026-01-19   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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