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: 340

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
313-340 A Detroit Zone 4 MI DTRTMIUVDS0  9323 MICHIGAN BELL TEL CO 340      
313-340 0 Detroit Zone 4 MI   9323 MICHIGAN BELL TEL CO 340      
313-340 1 Detroit Zone 4 MI   9323 MICHIGAN BELL TEL CO 340      
313-340 2 Detroit Zone 4 MI   516C AT&T CORP. 340   2013-01-03   
313-340 3 Detroit Zone 4 MI   9323 MICHIGAN BELL TEL CO 340      
313-340 4 Detroit Zone 4 MI   9323 MICHIGAN BELL TEL CO 340      
313-340 5 Detroit Zone 4 MI   9323 MICHIGAN BELL TEL CO 340      
313-340 6 Detroit Zone 4 MI   9323 MICHIGAN BELL TEL CO 340      
313-340 7 Detroit Zone 4 MI   9323 MICHIGAN BELL TEL CO 340      
313-340 8 Detroit Zone 4 MI   9323 MICHIGAN BELL TEL CO 340      
313-340 9 Detroit Zone 4 MI   318J COMCAST IP PHONE, LLC 340   2007-02-04   

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

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