Local Calling Guide

Area code/prefix search

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NPA: 331 [Rate centres in NPA 331] [Dial plan for NPA 331]

NXX: 346

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-346 A Naperville IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2026-07-20   
331-346 0 Naperville IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2026-07-20   
331-346 1 Naperville IL   224C ONVOY, LLC 358   2026-09-27   
331-346 2 Naperville IL   816C INTRADO COMMUNICATIONS, LLC 358   2026-10-16   
331-346 3 Naperville IL ELGNILOTGT5  5562 METROPCS, INC. 358   2026-07-21   
331-346 4 Naperville IL   984E BANDWIDTH.COM CLEC, LLC - IL 358   2026-11-07   
331-346 6 Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2026-09-27   
331-346 7 Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2026-09-27   
331-346 8 Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2026-09-27   
331-346 9 Naperville IL   984E BANDWIDTH.COM CLEC, LLC - IL 358   2026-10-02   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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