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 SFLDMIMKEMD  490J BOOST SUBSCRIBERCO L.L.C. 340   2025-05-30   
313-620 0 Detroit Zone 3 MI SFLDMIMKEMD  490J BOOST SUBSCRIBERCO L.L.C. 340   2025-05-30   
313-620 1 Detroit Zone 3 MI SFLDMIMKEMD  490J BOOST SUBSCRIBERCO L.L.C. 340   2025-09-28   
313-620 2 Detroit Zone 3 MI SFLDMIMKCMD  321J HD CARRIER LLC 340   2025-11-03   
313-620 3 Detroit Zone 3 MI SFLDMIMKEMD  490J BOOST SUBSCRIBERCO L.L.C. 340   2026-07-02   
313-620 7 Detroit Zone 3 MI   824J OPENTACT INC. 340   2026-10-10   

Last updated: Sun, 01 Nov 2026 02:11:49 UTC

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