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: 277

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
313-277 A Detroit Zone 6 MI DRBRMIDBDS0  9323 MICHIGAN BELL TEL CO 340      
313-277 0 Detroit Zone 6 MI   9323 MICHIGAN BELL TEL CO 340      
313-277 1 Detroit Zone 6 MI   9323 MICHIGAN BELL TEL CO 340      
313-277 2 Detroit Zone 6 MI   9323 MICHIGAN BELL TEL CO 340      
313-277 3 Detroit Zone 6 MI   9323 MICHIGAN BELL TEL CO 340      
313-277 4 Detroit Zone 6 MI   9323 MICHIGAN BELL TEL CO 340      
313-277 5 Detroit Zone 6 MI   9323 MICHIGAN BELL TEL CO 340      
313-277 6 Detroit Zone 6 MI   9323 MICHIGAN BELL TEL CO 340      
313-277 7 Detroit Zone 6 MI   9323 MICHIGAN BELL TEL CO 340      
313-277 8 Detroit Zone 6 MI   9323 MICHIGAN BELL TEL CO 340      
313-277 9 Detroit Zone 6 MI   543C ONVOY, LLCV - MI 340   2014-06-06   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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