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: 400

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
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 CHCGILWUDS4  063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358   2019-10-03   
331-400 2 Oswego IL CHCGIL24DS6  224C ONVOY, LLC 358   2021-08-12   
331-400 3 Oswego IL CHCGILNEXIX  506J TWILIO INTERNATIONAL, INC. 358   2021-04-13   
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 CHCGIL24DS6  224C ONVOY, LLC 358   2021-08-12   
331-400 7 Oswego IL CHCGIL24DS6  224C ONVOY, LLC 358   2021-08-12   
331-400 8 Oswego IL CHCGIL24XMD  495J STRATUS NETWORKS 358   2020-09-26   
331-400 9 Oswego IL   515J IP HORIZON LLC 358   2021-06-26   

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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