Local Calling Guide

Area code/prefix search

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

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
517-357 A CMBAMIXJRSA  4417 FRONTIER COMMUNICATIONS OF MICHIGAN, INC. 346      
517-946 A MDTPMICODS0  3535 ACD TELECOM, INC. - MI 346      
517-946 0   624H ONVOY SPECTRUM, LLC 346   2024-04-21   
517-946 2   543C ONVOY, LLCV - MI 346   2021-08-15   
517-946 3   3535 ACD TELECOM, INC. - MI 346      
517-946 4   543C ONVOY, LLCV - MI 346   2018-10-12   
517-946 6   543C ONVOY, LLCV - MI 346   2021-07-11   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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