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Removing Voters for Lack of Voting-Related Activity
Following a process required by the National Voter Registration Act of 1993, in all states, inactive voters can eventually be removed from the registration rolls. In most states, an indication of a voter's ineligibility"generally a move to an address outside the jurisdiction"starts a years-long process that can result in the removal of the voter from the registration list:

First, states must mail an address confirmation to the voter.
If the voter fails to respond within a specified period, in many states that voter is then placed on an inactive list.
Once on the inactive list, if the voter fails to vote, update his or her address, or engage in other election activity such as signing a candidate or initiative petition for a period including two federal general elections (four years), only then can election officials remove the voter from the registration list.