Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 231 [Rate centres in NPA 231] [Dial plan for NPA 231]

NXX: 370

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-370 A Muskegon MI GDRPMIBLXDZ  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS LLC DBA T-MOBILE USA 348   2021-11-05   
231-370 0 Muskegon MI   5562 METROPCS, INC. 348   2021-11-06   
231-370 5 Muskegon MI   543C ONVOY, LLCV - MI 348   2021-11-15   
231-370 6 Muskegon MI   543C ONVOY, LLCV - MI 348   2021-11-15   
231-370 7 Muskegon MI   543C ONVOY, LLCV - MI 348   2021-11-15   
231-370 8 Muskegon MI   2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS LLC DBA T-MOBILE USA 348   2021-11-05   
231-370 9 Muskegon MI   2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS LLC DBA T-MOBILE USA 348   2021-11-05   

Last updated: Fri, 01 Jul 2022 02:53:40 UTC

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