Local Calling Guide

Area code/prefix search

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Detroit Zone 4, MI

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
313-927 1 DTRTMIUVDS0  9323 MICHIGAN BELL TEL CO 340      
313-927 2 DTRTMIUVDS0  9323 MICHIGAN BELL TEL CO 340      
313-927 3 DTRTMIUVDS0  9323 MICHIGAN BELL TEL CO 340      
313-927 4 DTRTMIUVDS0  9323 MICHIGAN BELL TEL CO 340      
313-927 5 DTRTMIUVDS0  9323 MICHIGAN BELL TEL CO 340      
313-927 6 DTRTMIUVDS0  9323 MICHIGAN BELL TEL CO 340      
313-927 7 FLNTMICD0MD  829J PAETEC ITEL, LLC 340   2007-06-01   
313-927 8 DTRTMIUVDS0  9323 MICHIGAN BELL TEL CO 340      
313-927 9 DTRTMIUVDS0  9323 MICHIGAN BELL TEL CO 340      
313-931 A DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-933 A DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-934 A DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-934 0 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-934 1 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-934 2 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-934 3 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-934 4 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-934 5 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-934 6 LIVNMIUX8MD  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 340   2023-08-15   
313-934 7 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-934 8 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-934 9 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-935 A DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-935 0 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-935 1 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-935 2 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-935 3 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-935 4 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-935 5 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-935 6   145J TERRA NOVA TELECOM INC. 340   2021-09-24   
313-935 7 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-935 8 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-935 9 DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      

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Last updated: Wed, 04 Mar 2026 03:00:52 UTC

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