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: 620

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
313-620 A Detroit Zone 3 MI   490J BOOST SUBSCRIBERCO L.L.C. 340   2025-05-30   
313-620 0 Detroit Zone 3 MI   490J BOOST SUBSCRIBERCO L.L.C. 340   2025-05-30   
313-620 1 Detroit Zone 3 MI   490J BOOST SUBSCRIBERCO L.L.C. 340   2025-09-28   
313-620 2 Detroit Zone 3 MI   321J HD CARRIER LLC 340   2025-11-03   

Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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