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 DTRTMIVWDMD  624H ONVOY SPECTRUM, LLC 340   2021-07-18   
517-557 5 Britton MI   624H ONVOY SPECTRUM, LLC 340   2021-07-18   
517-557 7 Britton MI   543C ONVOY, LLCV - MI 340   2021-07-19   

Last updated: Fri, 01 Jul 2022 02:53:40 UTC

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