Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 313 [Rate centres in NPA 313] [Dial plan for NPA 313]

NXX: 830

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
313-830 A Detroit Zone 5 MI   543C ONVOY, LLCV - MI 340   2026-01-11   
313-830 0 Detroit Zone 5 MI   543C ONVOY, LLCV - MI 340   2026-01-11   
313-830 1 Detroit Zone 5 MI   543C ONVOY, LLCV - MI 340   2026-01-11   
313-830 2 Detroit Zone 5 MI   543C ONVOY, LLCV - MI 340   2026-01-11   
313-830 3 Detroit Zone 5 MI   543C ONVOY, LLCV - MI 340   2026-01-11   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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