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: 370

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
517-370 A Montgomery MI LNNGMIMNX5Z  543C ONVOY, LLCV - MI 346      
517-370 0 Montgomery MI LNNGMIMN00Z  624H ONVOY SPECTRUM, LLC 346   2024-05-10   
517-370 2 Montgomery MI LNNGMIMNX5Z  543C ONVOY, LLCV - MI 346   2023-09-03   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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