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: 396

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-396 A Cadillac MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348      
231-396 0 Cadillac MI   515J IP HORIZON LLC 348   2022-01-02   
231-396 1 Cadillac MI   991E BANDWIDTH.COM CLEC, LLC - MI 348   2022-03-03   
231-396 2 Cadillac MI   116F PENINSULA FIBER NETWORK, LLC - MI 348   2022-12-23   
231-396 3 Cadillac MI   543C ONVOY, LLCV - MI 348   2022-04-01   
231-396 4 Cadillac MI   543C ONVOY, LLCV - MI 348   2023-07-08   
231-396 5 Cadillac MI   543C ONVOY, LLCV - MI 348   2023-08-12   
231-396 6 Cadillac MI   543C ONVOY, LLCV - MI 348   2022-01-01   
231-396 7 Cadillac MI   543C ONVOY, LLCV - MI 348   2022-01-01   
231-396 8 Cadillac MI   991E BANDWIDTH.COM CLEC, LLC - MI 348   2022-03-03   
231-396 9 Cadillac MI   6003 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 348   2022-08-02   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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