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: 261

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-261 A Lemont IL ELGNILOT0MD  6529 T-MOBILE USA, INC. 358      
331-261 0 Lemont IL   495J STRATUS NETWORKS 358   2020-09-26   
331-261 2 Lemont IL   506J TWILIO INTERNATIONAL INC 358   2021-04-13   
331-261 8 Lemont IL   6529 T-MOBILE USA, INC. 358   2019-08-19   
331-261 9 Lemont IL   6529 T-MOBILE USA, INC. 358   2019-08-19   

Last updated: Sun, 04 Apr 2021 19:28:27 UTC

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