Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 906 [Rate centres in NPA 906] [Dial plan for NPA 906]

NXX: 257

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
906-257 A Crystal Falls MI HNCCMIMN3MD  543C ONVOY, LLCV - MI 342      
906-257 0 Crystal Falls MI   543C ONVOY, LLCV - MI 342   2021-02-03   
906-257 1 Crystal Falls MI   543C ONVOY, LLCV - MI 342   2021-02-03   
906-257 2 Crystal Falls MI   543C ONVOY, LLCV - MI 342   2020-05-10   
906-257 3 Crystal Falls MI   543C ONVOY, LLCV - MI 342   2020-05-10   
906-257 4 Crystal Falls MI   543C ONVOY, LLCV - MI 342   2020-05-10   
906-257 5 Crystal Falls MI   543C ONVOY, LLCV - MI 342   2020-05-10   
906-257 6 Crystal Falls MI   543C ONVOY, LLCV - MI 342   2019-02-09   
906-257 7 Crystal Falls MI   543C ONVOY, LLCV - MI 342   2020-09-13   
906-257 8 Crystal Falls MI   543C ONVOY, LLCV - MI 342   2020-09-12   
906-257 9 Crystal Falls MI   543C ONVOY, LLCV - MI 342   2020-09-12   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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