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: 666

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
313-666 A Detroit Zone 6 MI SFLDMITODS2  543C ONVOY, LLCV - MI 340      
313-666 0 Detroit Zone 6 MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2016-02-24   
313-666 1 Detroit Zone 6 MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2016-02-24   
313-666 2 Detroit Zone 6 MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2016-04-28   
313-666 3 Detroit Zone 6 MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2016-04-28   
313-666 4 Detroit Zone 6 MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2017-12-09   
313-666 5 Detroit Zone 6 MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2017-12-09   
313-666 6 Detroit Zone 6 MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2015-11-16   
313-666 7 Detroit Zone 6 MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2017-12-09   
313-666 8 Detroit Zone 6 MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2017-12-09   
313-666 9 Detroit Zone 6 MI SFLDMIMNXRX  991E BANDWIDTH.COM CLEC, LLC - MI 340   2019-01-11   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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