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: 821

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
313-821 A Detroit Zone 2 MI DTRTMILXDS0  9323 MICHIGAN BELL TEL CO 340      
313-821 0 Detroit Zone 2 MI DTRTMILXDS0  9323 MICHIGAN BELL TEL CO 340      
313-821 1 Detroit Zone 2 MI DTRTMILXDS0  9323 MICHIGAN BELL TEL CO 340      
313-821 2 Detroit Zone 2 MI DTRTMILXDS0  9323 MICHIGAN BELL TEL CO 340      
313-821 3 Detroit Zone 2 MI DTRTMILXDS0  9323 MICHIGAN BELL TEL CO 340      
313-821 4 Detroit Zone 2 MI WAYNMIMNXUX  318J COMCAST IP PHONE, LLC 340   2008-03-05   
313-821 5 Detroit Zone 2 MI DTRTMILXDS0  9323 MICHIGAN BELL TEL CO 340      
313-821 6 Detroit Zone 2 MI FLNTMICD0MD  829J PAETEC ITEL, LLC 340   2006-04-08   
313-821 7 Detroit Zone 2 MI SFLDMIDNDS5  9714 GRID 4 COMMUNICATIONS, INC. - MI 340   2006-09-21   
313-821 8 Detroit Zone 2 MI DTRTMILXDS0  9323 MICHIGAN BELL TEL CO 340      
313-821 9 Detroit Zone 2 MI DTRTMILXDS0  9323 MICHIGAN BELL TEL CO 340      

Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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