Tennessee is now required to give all its registered voters an option to vote by mail during the COVID-19 pandemic.
A judge made the ruling Thursday. She said limiting mail-in voting options would be an "unreasonable burden on the fundamental right to vote" because Tennesseans would have to weigh the risk of getting sick with not voting.
Typically, Tennessee's election code only allows certain people to vote by mail, such as those who have certain disabilities or are over 65.
The state has raised concerns that it'd be too expensive to expand mail-in voting for November's presidential election. It's expected to appeal the decision.
While President Donald Trump has been vocal against expanding vote-by-mail, some states have relaxed restrictions.
Last month, a Texas federal judge also decided to widely allow mail-in votes, ruling that voters deserve "the option to choose voting by letter carrier versus voting with disease carriers."
Additional reporting by Jonathan Matisse of The Associated Press.