Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Frontier, MI

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
517-254 A FRNTMIXIRSA  4417 FRONTIER COMMUNICATIONS OF MICHIGAN, INC. 346      
517-891 A MDTPMICODS0  3535 ACD TELECOM, INC. - MI 346      
517-891 0   624H ONVOY SPECTRUM, LLC 346   2024-05-03   
517-891 2   543C ONVOY, LLCV - MI 346   2021-07-11   
517-891 3   3535 ACD TELECOM, INC. - MI 346      
517-891 4   543C ONVOY, LLCV - MI 346   2021-08-15   
517-891 5   792K CHARTER IP ENABLED SERVICES, LLC 346   2026-02-22   
517-891 8   543C ONVOY, LLCV - MI 346   2018-10-12   

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

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