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: 417

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
313-417 A Detroit Zone 2 MI DTRTMINIDS0  9323 MICHIGAN BELL TEL CO 340      
313-417 0 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-417 1 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-417 2 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-417 3 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-417 4 Detroit Zone 2 MI   933G PEERLESS NETWORK OF MICHIGAN, LLC - MI 340   2022-03-31   
313-417 5 Detroit Zone 2 MI   543C ONVOY, LLCV - MI 340   2022-08-21   
313-417 6 Detroit Zone 2 MI   2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 340   2014-09-27   
313-417 7 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-417 8 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-417 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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