Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 517 [Rate centres in NPA 517] [Dial plan for NPA 517]

NXX: 557

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
517-557 A Britton MI ADRNMIXGMMD  624H ONVOY SPECTRUM, LLC 340      
517-557 5 Britton MI ADRNMIXGMMD  624H ONVOY SPECTRUM, LLC 340   2021-07-18   
517-557 7 Britton MI ADRNMIXGOMD  543C ONVOY, LLCV - MI 340   2021-07-19   
517-557 9 Britton MI SFLDMIMKDS2  933G PEERLESS NETWORK OF MICHIGAN, LLC - MI 340   2023-08-19   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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