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: 857

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
313-857 A Detroit Zone 6 MI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 340   2025-10-20   
313-857 0 Detroit Zone 6 MI   490J BOOST SUBSCRIBERCO L.L.C. 340   2026-01-29   
313-857 1 Detroit Zone 6 MI   490J BOOST SUBSCRIBERCO L.L.C. 340   2026-03-29   
313-857 2 Detroit Zone 6 MI   321J HD CARRIER LLC 340   2025-11-03   
313-857 3 Detroit Zone 6 MI   490J BOOST SUBSCRIBERCO L.L.C. 340   2026-04-28   
313-857 4 Detroit Zone 6 MI   490J BOOST SUBSCRIBERCO L.L.C. 340   2026-06-27   
313-857 5 Detroit Zone 6 MI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 340   2025-10-20   
313-857 6 Detroit Zone 6 MI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 340   2025-10-20   
313-857 7 Detroit Zone 6 MI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 340   2025-10-20   
313-857 8 Detroit Zone 6 MI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 340   2025-10-20   
313-857 9 Detroit Zone 6 MI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 340   2025-10-20   

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

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