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: 331

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-331 A Aurora IL   224C ONVOY, LLC 358   2025-10-17   
331-331 0 Aurora IL   224C ONVOY, LLC 358   2025-10-17   
331-331 1 Aurora IL   224C ONVOY, LLC 358   2025-10-17   
331-331 2 Aurora IL   224C ONVOY, LLC 358   2025-10-17   
331-331 3 Aurora IL   224C ONVOY, LLC 358   2025-10-17   
331-331 4 Aurora IL   224C ONVOY, LLC 358   2025-10-17   
331-331 5 Aurora IL   224C ONVOY, LLC 358   2025-10-17   
331-331 6 Aurora IL   224C ONVOY, LLC 358   2025-10-17   
331-331 7 Aurora IL   224C ONVOY, LLC 358   2025-10-17   
331-331 8 Aurora IL   224C ONVOY, LLC 358   2025-10-17   
331-331 9 Aurora IL   224C ONVOY, LLC 358   2025-10-17   

Last updated: Mon, 15 Sep 2025 02:24:40 UTC

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