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: 255

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-255 A Aurora IL CHCGIL24DS6  224C ONVOY, LLC 358      
331-255 0 Aurora IL CHCGIL24DS6  224C ONVOY, LLC 358   2017-10-22   
331-255 1 Aurora IL CHCGIL24DS6  224C ONVOY, LLC 358   2017-10-22   
331-255 2 Aurora IL CHCGIL24DS6  224C ONVOY, LLC 358   2017-10-22   
331-255 3 Aurora IL CHCGIL24DS6  224C ONVOY, LLC 358   2017-10-22   
331-255 4 Aurora IL CHCGIL24DS6  224C ONVOY, LLC 358   2017-10-22   
331-255 5 Aurora IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2018-11-10   
331-255 6 Aurora IL WCHCILBFGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2018-04-07   
331-255 7 Aurora IL WCHCILBFGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2018-01-22   
331-255 8 Aurora IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2018-11-10   
331-255 9 Aurora IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2018-11-10   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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