Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 586 [Rate centres in NPA 586] [Dial plan for NPA 586]

NXX: 304

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
586-304 A New Haven MI SFLDMITODS2  543C ONVOY, LLCV - MI 340      
586-304 0 New Haven MI   624H ONVOY SPECTRUM, LLC 340   2021-12-02   
586-304 1 New Haven MI   624H ONVOY SPECTRUM, LLC 340   2021-12-02   
586-304 2 New Haven MI   543C ONVOY, LLCV - MI 340   2023-07-02   
586-304 4 New Haven MI   543C ONVOY, LLCV - MI 340   2021-08-26   
586-304 6 New Haven MI   933G PEERLESS NETWORK OF MICHIGAN, LLC - MI 340   2022-12-17   
586-304 7 New Haven MI   933G PEERLESS NETWORK OF MICHIGAN, LLC - MI 340   2023-06-22   
586-304 8 New Haven MI   490J DISH WIRELESS, LLC 340   2023-02-27   

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

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