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: 345

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-345 A Naperville IL CHCGILWURMD  965H FRACTEL, LLC 358      
331-345 0 Naperville IL   515J IP HORIZON LLC 358   2021-06-12   
331-345 1 Naperville IL   939H COMMIO, LLC 358   2021-10-14   
331-345 2 Naperville IL   939H COMMIO, LLC 358   2021-10-14   
331-345 3 Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2024-10-11   
331-345 4 Naperville IL   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2022-06-18   
331-345 5 Naperville IL   939H COMMIO, LLC 358   2021-10-14   
331-345 6 Naperville IL   965H FRACTEL, LLC 358   2021-01-17   
331-345 7 Naperville IL   939H COMMIO, LLC 358   2021-10-14   
331-345 8 Naperville IL   939H COMMIO, LLC 358   2021-10-14   
331-345 9 Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2022-01-10   

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

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