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: 777

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
313-777 A Detroit Zone 3 MI SFLDMITODS2  543C ONVOY, LLCV - MI 340      
313-777 0 Detroit Zone 3 MI   543C ONVOY, LLCV - MI 340   2015-07-27   
313-777 1 Detroit Zone 3 MI   543C ONVOY, LLCV - MI 340   2015-07-27   
313-777 2 Detroit Zone 3 MI   543C ONVOY, LLCV - MI 340   2015-07-27   
313-777 3 Detroit Zone 3 MI   543C ONVOY, LLCV - MI 340   2015-07-27   
313-777 4 Detroit Zone 3 MI   543C ONVOY, LLCV - MI 340   2015-07-27   
313-777 5 Detroit Zone 3 MI   543C ONVOY, LLCV - MI 340   2015-07-27   
313-777 6 Detroit Zone 3 MI   543C ONVOY, LLCV - MI 340   2015-07-27   
313-777 7 Detroit Zone 3 MI   543C ONVOY, LLCV - MI 340   2015-04-20   
313-777 8 Detroit Zone 3 MI   543C ONVOY, LLCV - MI 340   2015-04-20   
313-777 9 Detroit Zone 3 MI   543C ONVOY, LLCV - MI 340   2015-07-27   

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

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