Once properly registered to vote in Tennessee, a person remains permanently registered unless the Election Commission must remove the registration from its records as a result of acts requiring purging a voter. T.C.A. 2-2-105 and 2-2-106

Acts Requiring Purging a Voter

The registration of a voter shall be purged:

• upon receipt of a request from the voter to purge 
  
• ​upon learning that the voter has had a name change for ninety (90) days or more, except by marriage, and the voter has failed to notify the election commission.
  
• ​upon the death of the voter
  
• ​upon receiving official notice that the voter has been convicted of an infamous crime as defined in T.C.A. 40-20-112
  
• ​upon written confirmation that the voter has moved outside of the county of registration or has registered to vote in another jurisdiction
  
• ​if the voter fails to respond to a confirmation notice, or if the voter fails to otherwise update the voter registration over the period of two (2) regular November elections following the date the notice was first sent