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: 305

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
517-305 A Clarklake MI LNNGMIVE2MD  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 346      
517-305 0 Clarklake MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 346   2008-10-31   
517-305 1 Clarklake MI   543C ONVOY, LLCV - MI 346   2016-04-02   
517-305 2 Clarklake MI   543C ONVOY, LLCV - MI 346   2012-10-14   
517-305 3 Clarklake MI   770E TELEPORT COMMUNICATIONS AMERICA, LLC - MI 346   2016-03-21   
517-305 4 Clarklake MI   543C ONVOY, LLCV - MI 346   2013-01-30   
517-305 6 Clarklake MI   516C AT&T CORP. 346   2011-09-30   
517-305 7 Clarklake MI   508J CENTURYLINK COMMUNICATIONS, LLC 346   2016-01-01   
517-305 8 Clarklake MI   543C ONVOY, LLCV - MI 346   2016-04-02   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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