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: 342

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-342 A Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2026-01-22   
331-342 0 Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2026-01-22   
331-342 1 Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2026-01-22   
331-342 8 Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2026-01-23   
331-342 9 Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2026-01-23   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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