Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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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 0   9323 MICHIGAN BELL TEL CO 340      
313-927 1   9323 MICHIGAN BELL TEL CO 340      
313-927 2   9323 MICHIGAN BELL TEL CO 340      
313-927 3   9323 MICHIGAN BELL TEL CO 340      
313-927 4   9323 MICHIGAN BELL TEL CO 340      
313-927 5   9323 MICHIGAN BELL TEL CO 340      
313-927 6   9323 MICHIGAN BELL TEL CO 340      
313-927 7   829J PAETEC ITEL, LLC 340   2007-06-01   
313-927 8   9323 MICHIGAN BELL TEL CO 340      
313-927 9   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   9323 MICHIGAN BELL TEL CO 340      
313-934 1   9323 MICHIGAN BELL TEL CO 340      
313-934 2   9323 MICHIGAN BELL TEL CO 340      
313-934 3   9323 MICHIGAN BELL TEL CO 340      
313-934 4   9323 MICHIGAN BELL TEL CO 340      
313-934 5   9323 MICHIGAN BELL TEL CO 340      
313-934 6   2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 340   2023-08-15   
313-934 7   9323 MICHIGAN BELL TEL CO 340      
313-934 8   9323 MICHIGAN BELL TEL CO 340      
313-934 9   9323 MICHIGAN BELL TEL CO 340      
313-935 A DTRTMIHGDS0  9323 MICHIGAN BELL TEL CO 340      
313-935 0   9323 MICHIGAN BELL TEL CO 340      
313-935 1   9323 MICHIGAN BELL TEL CO 340      
313-935 2   9323 MICHIGAN BELL TEL CO 340      
313-935 3   9323 MICHIGAN BELL TEL CO 340      
313-935 4   9323 MICHIGAN BELL TEL CO 340      
313-935 5   9323 MICHIGAN BELL TEL CO 340      
313-935 6   145J TERRA NOVA TELECOM INC. 340   2021-09-24   
313-935 7   9323 MICHIGAN BELL TEL CO 340      
313-935 8   9323 MICHIGAN BELL TEL CO 340      
313-935 9   9323 MICHIGAN BELL TEL CO 340      

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

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