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: 307

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-307 A Lombard IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      
331-307 0 Lombard IL CHCGIL24DS6  224C ONVOY, LLC 358   2015-08-29   
331-307 1 Lombard IL CHCGIL24DS6  224C ONVOY, LLC 358   2016-02-15   
331-307 2 Lombard IL CHCGIL24DS6  224C ONVOY, LLC 358   2016-02-15   
331-307 3 Lombard IL CHCGIL24DS6  224C ONVOY, LLC 358   2016-03-02   
331-307 4 Lombard IL CHCGIL24DS6  224C ONVOY, LLC 358   2016-05-01   
331-307 5 Lombard IL CHCGIL24DS6  224C ONVOY, LLC 358   2016-05-01   
331-307 6 Lombard IL   515J IP HORIZON LLC 358   2016-08-09   
331-307 7 Lombard IL CHCGILNEXJX  318J COMCAST IP PHONE, LLC 358   2015-08-20   
331-307 8 Lombard IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2014-12-08   
331-307 9 Lombard IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2014-12-08   

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

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