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: 316

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-316 A Naperville IL CHCGILWUKMD  939H COMMIO, LLC 358   2024-03-09   
331-316 0 Naperville IL   939H COMMIO, LLC 358   2024-03-09   
331-316 1 Naperville IL   939H COMMIO, LLC 358   2024-03-09   
331-316 2 Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2024-05-10   
331-316 3 Naperville IL   224C ONVOY, LLC 358   2024-05-24   
331-316 4 Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2024-06-08   
331-316 5 Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2024-06-08   
331-316 6 Naperville IL   224C ONVOY, LLC 358   2024-03-11   
331-316 7 Naperville IL   224C ONVOY, LLC 358   2024-03-11   
331-316 8 Naperville IL   224C ONVOY, LLC 358   2024-03-11   
331-316 9 Naperville IL   224C ONVOY, LLC 358   2024-03-11   

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

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