The secretary of state's office is sending out postcards this week to nearly 178,000 voters to update registration information.
Secretary of State Dianna Duran says the effort is to clean up voter files in compliance with federal law, but it won't affect anyone until after the 2014 elections.
The postcards are going to people who've notified the Postal Service of a change of address or had previous election mailings returned as undeliverable.
People who don't return the postcards to update their addresses and don't vote in a general election through 2014 will have their names removed from voter rolls.
Duran says the process of purging non-residents and non-voters hasn't been completed in more than seven years, and as many as 170,000 people could end up being removed from voter rolls.