Local Calling Guide

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Search area code/prefix (NPA/NXX)
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NPA: 331 [Rate centres in NPA 331] [Dial plan for NPA 331]

NXX: 529

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-529 A Naperville IL CHCGILWURMD  965H FRACTEL, LLC 358      
331-529 0 Naperville IL   063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358   2020-02-26   
331-529 1 Naperville IL   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2020-03-11   
331-529 2 Naperville IL   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2020-03-11   
331-529 3 Naperville IL   965H FRACTEL, LLC 358   2019-10-02   
331-529 4 Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2022-01-10   
331-529 5 Naperville IL   224C ONVOY, LLC 358   2020-12-03   
331-529 6 Naperville IL   224C ONVOY, LLC 358   2020-12-03   
331-529 7 Naperville IL   224C ONVOY, LLC 358   2020-12-03   
331-529 8 Naperville IL   224C ONVOY, LLC 358   2020-12-03   
331-529 9 Naperville IL   965H FRACTEL, LLC 358   2019-10-02   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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