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: 823

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
313-823 A Detroit Zone 2 MI DTRTMILXDS0  9323 MICHIGAN BELL TEL CO 340      
313-823 0 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-823 1 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-823 2 Detroit Zone 2 MI   543C ONVOY, LLCV - MI 340   2022-08-21   
313-823 3 Detroit Zone 2 MI   543C ONVOY, LLCV - MI 340   2022-08-21   
313-823 4 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-823 6 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-823 7 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-823 8 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-823 9 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      

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

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