Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 331 [Rate centres in NPA 331] [Dial plan for NPA 331]

NXX: 328

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-328 A Naperville IL BFGVILASG00  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2025-01-30   
331-328 8 Naperville IL   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2025-04-12   
331-328 9 Naperville IL BFGVILASG00  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2025-01-30   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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