Burnley sign England youngster Ramsey from Villa on five-year deal
No financial details have been disclosed but British media reported Burnley would pay Villa £14 million for Ramsey.
"I'm absolutely buzzing," Ramsey told the club website.
"I have been waiting to be a Burnley player for a while now and I'm really happy it's all officially done now. I can't wait to get started. I can't wipe my smile off my face."
Ramsey, who moved through Villa's youth ranks, was a regular for their under-21 side in recent seasons with whom he won the FA Youth Cup in 2021.
He spent the 2022-23 campaign on loan with Norwich City and Middlesbrough in the Championship.
Ramsey earned more than 30 caps with England youth teams, winning the under-19 European Championship in 2022.