Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

Switch: DTRTMINIDS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
313-343 A Detroit Zone 2 MI 9323 MICHIGAN BELL TEL CO 340      
313-417 A Detroit Zone 2 MI 9323 MICHIGAN BELL TEL CO 340      
313-473 A Detroit Zone 2 MI 9323 MICHIGAN BELL TEL CO 340      
313-640 A Detroit Zone 2 MI 9323 MICHIGAN BELL TEL CO 340      
313-642 A Detroit Zone 2 MI 9323 MICHIGAN BELL TEL CO 340      
313-647 A Detroit Zone 2 MI 9323 MICHIGAN BELL TEL CO 340      
313-881 A Detroit Zone 2 MI 9323 MICHIGAN BELL TEL CO 340      
313-882 A Detroit Zone 2 MI 9323 MICHIGAN BELL TEL CO 340      
313-884 A Detroit Zone 2 MI 9323 MICHIGAN BELL TEL CO 340      
313-885 A Detroit Zone 2 MI 9323 MICHIGAN BELL TEL CO 340      
313-886 A Detroit Zone 2 MI 9323 MICHIGAN BELL TEL CO 340      

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

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