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: 221

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
313-221 A Detroit Zone 1 MI DTRTMIBHDS1  9323 MICHIGAN BELL TEL CO 340      
313-221 0 Detroit Zone 1 MI LIVNMIUX0MD  5562 METROPCS, INC. 340   2008-03-07   
313-221 1 Detroit Zone 1 MI FLNTMICD0MD  829J PAETEC ITEL, LLC 340   2006-04-03   
313-221 2 Detroit Zone 1 MI DTRTMIBHDS1  9323 MICHIGAN BELL TEL CO 340   2005-07-17   
313-221 3 Detroit Zone 1 MI LIVNMIUX0MD  5562 METROPCS, INC. 340   2006-08-12   
313-221 4 Detroit Zone 1 MI LIVNMIUX0MD  5562 METROPCS, INC. 340   2005-11-10   
313-221 5 Detroit Zone 1 MI SFLDMIDNDS6  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340   2010-05-17   
313-221 6 Detroit Zone 1 MI LIVNMIUX8MD  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 340   2016-08-07   
313-221 7 Detroit Zone 1 MI LIVNMIUX8MD  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 340   2015-07-03   
313-221 8 Detroit Zone 1 MI SFLDMIDNDS6  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340   2006-01-08   
313-221 9 Detroit Zone 1 MI SFLDMIDNDS6  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340   2006-01-08   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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