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 2 Naperville IL   321J HD CARRIER LLC 358   2026-03-08   
331-342 3 Naperville IL   321J HD CARRIER LLC 358   2026-03-08   
331-342 4 Naperville IL   321J HD CARRIER LLC 358   2026-03-08   
331-342 5 Naperville IL   224C ONVOY, LLC 358   2026-02-20   
331-342 6 Naperville IL   984E BANDWIDTH.COM CLEC, LLC - IL 358   2026-05-03   
331-342 7 Naperville IL   224C ONVOY, LLC 358   2026-05-31   
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: Sun, 17 May 2026 03:26:51 UTC

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