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: 921

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
517-921 A Addison MI MDTPMICODS0  3535 ACD TELECOM, INC. - MI 346      
517-921 0 Addison MI LNNGMIMNX5Z  543C ONVOY, LLCV - MI 346   2020-02-10   
517-921 1 Addison MI LNNGMIMNX5Z  543C ONVOY, LLCV - MI 346   2020-02-10   
517-921 2 Addison MI MDTPMICODS0  3535 ACD TELECOM, INC. - MI 346      
517-921 3 Addison MI MDTPMICODS0  3535 ACD TELECOM, INC. - MI 346      
517-921 4 Addison MI MDTPMICODS0  3535 ACD TELECOM, INC. - MI 346      
517-921 5 Addison MI LNNGMIVE2MD  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 346   2018-05-18   
517-921 6 Addison MI LNNGMIMNXQZ  508J CENTURYLINK COMMUNICATIONS, LLC 346   2016-01-25   
517-921 7 Addison MI MDTPMICODS0  3535 ACD TELECOM, INC. - MI 346      
517-921 8 Addison MI LNNGMIMNX4Z  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 346   2009-09-26   
517-921 9 Addison MI MDTPMICODS0  3535 ACD TELECOM, INC. - MI 346      

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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