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

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NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-385 2 Aurora IL   6529 T-MOBILE USA, INC. 358   2017-01-06   
331-385 3 Aurora IL   6529 T-MOBILE USA, INC. 358   2017-01-06   
331-385 4 Aurora IL   6529 T-MOBILE USA, INC. 358   2017-01-06   
331-385 5 Aurora IL   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2016-12-24   
331-385 6 Aurora IL   224C ONVOY, LLC 358   2017-03-01   
331-385 7 Aurora IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2017-03-24   
331-385 8 Aurora IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2017-03-24   
331-385 9 Aurora IL   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2016-11-12   
331-388 A Sugar Grove IL CHCGILWURMD  965H FRACTEL, LLC 358      
331-388 0 Sugar Grove IL   073H TELNYX LLC 358   2022-12-05   
331-388 1 Sugar Grove IL   6529 T-MOBILE USA, INC. 358   2023-02-11   
331-388 2 Sugar Grove IL   6529 T-MOBILE USA, INC. 358   2023-02-11   
331-388 3 Sugar Grove IL   224C ONVOY, LLC 358   2023-07-03   
331-388 4 Sugar Grove IL   224C ONVOY, LLC 358   2024-03-14   
331-388 5 Sugar Grove IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2025-08-28   
331-388 7 Sugar Grove IL   224C ONVOY, LLC 358   2022-02-27   
331-388 8 Sugar Grove IL   965H FRACTEL, LLC 358   2021-03-26   
331-388 9 Sugar Grove IL   224C ONVOY, LLC 358   2023-09-07   
331-399 A Downers Grove IL CHCGILWURMD  965H FRACTEL, LLC 358      
331-399 0 Downers Grove IL   515J IP HORIZON LLC 358   2021-06-12   
331-399 1 Downers Grove IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2021-09-29   
331-399 2 Downers Grove IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2021-09-29   
331-399 3 Downers Grove IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2024-11-22   
331-399 4 Downers Grove IL   624H ONVOY SPECTRUM, LLC 358   2021-06-28   
331-399 5 Downers Grove IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2021-09-29   
331-399 6 Downers Grove IL   7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358   2021-03-27   
331-399 7 Downers Grove IL   624H ONVOY SPECTRUM, LLC 358   2021-11-14   
331-399 8 Downers Grove IL   624H ONVOY SPECTRUM, LLC 358   2021-11-14   
331-399 9 Downers Grove IL   965H FRACTEL, LLC 358   2021-03-26   
331-400 A Oswego IL CHCGILWURMD  965H FRACTEL, LLC 358      
331-400 0 Oswego IL   965H FRACTEL, LLC 358   2019-10-02   
331-400 1 Oswego IL   063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358   2019-10-03   
331-400 2 Oswego IL   224C ONVOY, LLC 358   2021-08-12   
331-400 3 Oswego IL   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2024-11-22   
331-400 4 Oswego IL   965H FRACTEL, LLC 358   2019-10-02   
331-400 5 Oswego IL   224C ONVOY, LLC 358   2024-04-05   
331-400 6 Oswego IL   224C ONVOY, LLC 358   2021-08-12   
331-400 7 Oswego IL   224C ONVOY, LLC 358   2021-08-12   
331-400 8 Oswego IL   495J STRATUS NETWORKS 358   2020-09-26   
331-400 9 Oswego IL   515J IP HORIZON LLC 358   2021-06-26   
331-401 A Naperville IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
331-401 0 Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2017-08-15   
331-401 1 Naperville IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2016-02-04   
331-401 2 Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2017-01-22   
331-401 3 Naperville IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2016-02-22   
331-401 4 Naperville IL   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2016-06-13   
331-401 5 Naperville IL   318J COMCAST IP PHONE, LLC 358   2016-02-05   
331-401 6 Naperville IL   224C ONVOY, LLC 358   2017-02-13   
331-401 7 Naperville IL   6529 T-MOBILE USA, INC. 358   2017-04-13   
331-401 8 Naperville IL   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2016-09-14   

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

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