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: 273

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-273 A Lemont IL CHCGIL24DS6  224C ONVOY, LLC 358      
331-273 0 Lemont IL CHCGILWUKMD  939H COMMIO, LLC 358   2021-10-14   
331-273 1 Lemont IL CHCGILWUKMD  939H COMMIO, LLC 358   2021-10-14   
331-273 2 Lemont IL CHCGILWUKMD  939H COMMIO, LLC 358   2021-10-14   
331-273 3 Lemont IL CHCGIL24DS6  224C ONVOY, LLC 358   2021-08-08   
331-273 4 Lemont IL CHCGIL24DS6  224C ONVOY, LLC 358   2021-11-19   
331-273 5 Lemont IL CHCGIL24DS6  224C ONVOY, LLC 358   2021-11-19   
331-273 6 Lemont IL CHCGIL24DS6  224C ONVOY, LLC 358   2021-11-19   
331-273 7 Lemont IL CHCGILWUKMD  939H COMMIO, LLC 358   2021-10-14   
331-273 8 Lemont IL CHCGILWUKMD  939H COMMIO, LLC 358   2021-10-14   
331-273 9 Lemont IL CHCGILWUDS4  063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358   2021-10-01   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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