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: 922

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
313-922 A Detroit Zone 2 MI DTRTMIPEDS0  9323 MICHIGAN BELL TEL CO 340      
313-922 0 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-922 1 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-922 2 Detroit Zone 2 MI   991E BANDWIDTH.COM CLEC, LLC - MI 340   2018-10-18   
313-922 3 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-922 4 Detroit Zone 2 MI   516C AT&T CORP. 340   2013-01-21   
313-922 5 Detroit Zone 2 MI   7279 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI 340   2011-09-25   
313-922 6 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-922 7 Detroit Zone 2 MI   543C ONVOY, LLCV - MI 340   2014-10-22   
313-922 8 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      
313-922 9 Detroit Zone 2 MI   9323 MICHIGAN BELL TEL CO 340      

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

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