Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 517 [Rate centres in NPA 517] [Dial plan for NPA 517]

NXX: 244

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
517-244 A Mason MI MASNMIMSRSA  9323 MICHIGAN BELL TEL CO 346      
517-244 0 Mason MI   9323 MICHIGAN BELL TEL CO 346      
517-244 1 Mason MI   9323 MICHIGAN BELL TEL CO 346      
517-244 2 Mason MI   9323 MICHIGAN BELL TEL CO 346      
517-244 3 Mason MI   9323 MICHIGAN BELL TEL CO 346      
517-244 4 Mason MI   9323 MICHIGAN BELL TEL CO 346      
517-244 5 Mason MI   7157 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI 346   2004-03-16   
517-244 6 Mason MI   7157 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI 346   2006-04-15   
517-244 7 Mason MI   7157 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI 346   2004-09-05   
517-244 8 Mason MI   9323 MICHIGAN BELL TEL CO 346      
517-244 9 Mason MI   9323 MICHIGAN BELL TEL CO 346      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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