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: 270

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
313-270 A Detroit Zone 4 MI DTRTMIVTDS0  9323 MICHIGAN BELL TEL CO 340      
313-270 0 Detroit Zone 4 MI   829J PAETEC ITEL, LLC 340   2006-04-14   
313-270 1 Detroit Zone 4 MI   9323 MICHIGAN BELL TEL CO 340      
313-270 2 Detroit Zone 4 MI   9323 MICHIGAN BELL TEL CO 340      
313-270 3 Detroit Zone 4 MI   9323 MICHIGAN BELL TEL CO 340      
313-270 4 Detroit Zone 4 MI   9323 MICHIGAN BELL TEL CO 340      
313-270 5 Detroit Zone 4 MI   829J PAETEC ITEL, LLC 340   2008-07-05   
313-270 6 Detroit Zone 4 MI   197D VONAGE AMERICA LLC 340   2024-05-26   
313-270 7 Detroit Zone 4 MI   516C AT&T CORP. 340   2008-11-25   
313-270 8 Detroit Zone 4 MI   961J WOW! INTERNET, CABLE AND PHONE 340   2007-08-02   
313-270 9 Detroit Zone 4 MI   2550 123.NET, LLC 340   2008-04-18   

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

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